home

Archive for the 'supramolecular chemistry and molecular building blocks' Category

Commensurate Urea Inclusion Crystals With The Guest (E,E)‐1,4-Diiodo-1,3-Butadiene

Friday, December 20th, 2013

Published in Crystal Growth & Design (Cryst. Growth Des., 2013, 13 (9), pp. 3852–3855) earlier this year. The theory work is less impressive than the successful crystal growth, with initial solid-state efforts in Crystal09 only very recently now producing good results (leaving the molecular calculations to Gaussian09 in this paper). The procedure leading to the observed crystal structure of this inclusion complex is a significant step in the direction of testing the theory proposed in Bond Alternation In Infinite Periodic Polyacetylene: Dynamical Treatment Of The Anharmonic Potential published earlier this year in J. Mol. Struct.

2013dec20_DIBD_UIC

Caption: Two views along the ba and ca crystal axes of the (E,E)‐1,4-Diiodo-1,3-Butadiene : Urea Inclusion Complex.

Amanda F. Lashua, Tiffany M. Smith, Hegui Hu, Lihui Wei, Damian G. Allis, Michael B. Sponsler, and Bruce S. Hudson

Abstract: The urea inclusion compound (UIC) with (E,E)-1,4-diiodo-1,3-butadiene (DIBD) as a guest (DIBD:UIC) has been prepared and crystallographically characterized at 90 and 298 K as a rare example of a commensurate, fully ordered UIC. The crystal shows nearly hexagonal channels in the monoclinic space group P21/n. The DIBD guest molecules are arranged end-to-end with the nonbonding iodine atoms in the van der Waals contact. The guest structure is compared with that for DIBD at 90 K and with computations for the periodic UIC and isolated DIBD molecule.

NAMOT Pre-Release 2.2.0-pre4 In OSX 10.8 (Maybe Older Versions)

Sunday, January 13th, 2013

A recent visit to the College of Nanoscale Science and Engineering (CNSE) at SUNY Albany inspired a few new DNA ideas that I decided would be greatly simplified by having NAMOT available again for design. Having failed at the base install of the NAMOT 2 version and, unfortunately, not having NAMOT available in Fink for a simple installation, the solution became to build the pre-release from scratch. Ignoring the many errors one encounters while walking through an OSX/Xcode/Fink/X11 bootstrap, the final procedure worked well and without major problem. As usual, the error messages at varied steps are provided below because, I assume, those messages are what you’re searching for when you find your way here.

0. Required Installations

You’ll need the following installed for this particular build. I believe XCode is the only thing that you’ll have to pay for (if you don’t already have it. I seem to remember paying $5 through the App Store).

1. XCode

The OSX Developer Suite – developer.apple.com/xcode

2. XQuartz

An OSX (X.Org) X Window System – xquartz.macosforge.org/landing/

3. Fink

An OSX port program for a host of Unix codes and libraries – www.finkproject.org

3a. GSL

The GNU Scientific (C and C++) Libraries – www.gnu.org/software/gsl. This will be installed with Fink.

3b. LessTif

An OSF/Motif clone (made available for OSX through Fink) – lesstif.sourceforge.net. This will be installed with Fink.

4. NAMOT2.2.0-pre4

The -pre4 is currently available (from 2003) from sourceforge.net/projects/namot/files/. I did not try -pre3 and had no luck with the official 2 release.

And, with that…

1. XCode

Blindly follow the install procedure. Several steps below deal with working around the default install locations (specifically, /sw).

2. XQuartz

If you don’t have XQuartz installed, you’re configure step…

cd Downloads
cd namot-2.2.0-pre4
./configure 

will produce the following error…

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
...
creating libtool
checking for X... no
checking for main in -lX11... no
NAMOT requires Xwindows

Blindly follow the XQuartz install process. After the installations, you’ll receive the same error as above. The –x-libraries= and –x-includes= additions to configure below direct the script to the proper libraries and includes.

./configure --x-libraries=/usr/X11/lib/ --x-includes=/usrX11/include/

Hopefully, you’ll find yourself past the first install problem and onto the second problem.

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
...
creating libtool
checking for X... libraries /usr/X11/lib/, headers /usrX11/include/
checking for gethostbyname... yes
checking for connect... yes
checking for remove... yes
checking for shmat... yes
checking for IceConnectionNumber in -lICE... yes
checking for main in -lX11... yes
checking for main in -lgslcblas... no
NAMOT requires GNU Scientific Library

3. Fink

The next two codes that need to be installed are the GNU Scientific Libraries and LessTif, both of which are much easier to install using Fink. It is generally useful for many other codes as well, so a good program for any computational chemist to have on hand. The install should be non-problematic despite having to build it from source in 10.6 – 10.8 (as of January 2013). If you build with all the default settings, you’ll have no trouble after.

cd Downloads
cd fink-0.34.4
./bootstrap 

I chose the default settings throughout.

Fink must be installed and run with superuser (root) privileges. Fink can automatically try to become root when it's run from a user account. Since you're currently running this script as a normal user, the method you choose will also be used immediately for this script. Available methods:

(1)	Use sudo
(2)	Use su
(3)	None, fink must be run as root

Choose a method: [1] 

...

You should now have a working Fink installation in '/sw'. You still need package descriptions if you want to compile packages yourself. You can get them by running either of the commands: 'fink selfupdate-rsync', to update via rsync (generally preferred); or 'fink selfupdate-cvs', to update via CVS (more likely to work through a firewall).

Run '. /sw/bin/init.sh' to set up this terminal session environment to use Fink. To make the software installed by Fink available in all of your future terminal shells, add '. /sw/bin/init.sh' to the init script '.profile' or '.bash_profile' in your home directory. The program /sw/bin/pathsetup.sh can help with this. Enjoy.

Then you run the final step in Fink below:

/sw/bin/pathsetup.sh

Which will produce the following two pop-ups notifying you of shell modifications.

3a. GSL

With the install of Fink, you need to install GSL and LessTif. If you try to install either immediately after installation…

fink install gsl

…you’ll receive the following error:

Password:
Scanning package description files..........
Information about 305 packages read in 0 seconds.
no package found for "gsl"
Failed: no package found for specification 'gsl'!

Required after the installation is a fink selfupdate.

fink selfupdate

As usual, follow the default settings…

fink needs you to choose a SelfUpdateMethod.

(1)	cvs
(2)	Stick to point releases
(3)	rsync

Choose an update method [3] 
/usr/bin/find /sw/fink -name CVS -type d -print0 | xargs -0 /bin/rm -rf
fink is setting your default update method to rsync
...
Updating the list of locally available binary packages.
Scanning dists/stable/main/binary-darwin-i386
New package: dists/stable/main/binary-darwin-i386/base/base-files_1.9.13-1_darwin-i386.deb
New package: dists/stable/main/binary-darwin-i386/base/fink-mirrors_0.34.4.1-1_darwin-i386.deb

Which then leads to a successful GSL install.

fink install gsl

Producing the following output…

Information about 12051 packages read in 1 seconds.
The package 'gsl' will be built and installed.
Reading build dependency for gsl-1.15-1...
Reading dependency for gsl-1.15-1...
Reading runtime dependency for gsl-1.15-1...
Reading dependency for gsl-shlibs-1.15-1...
...
Updating the list of locally available binary packages.
Scanning dists/stable/main/binary-darwin-i386
New package: dists/stable/main/binary-darwin-i386/sci/gsl-shlibs_1.15-1_darwin-i386.deb
New package: dists/stable/main/binary-darwin-i386/sci/gsl_1.15-1_darwin-i386.deb

Attempting a fresh build after the GSL step…

./configure --x-libraries=/usr/X11/lib/ --x-includes=/usrX11/include/

…then still produces the following error:

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
...
checking for IceConnectionNumber in -lICE... yes
checking for main in -lX11... yes
checking for main in -lgslcblas... no
NAMOT requires GNU Scientific Library

As mentioned above, there are a few redirects that need to be made after the XCode / Fink install to put libraries and includes where, in this case, NAMOT expects them. To perform this task, we’ll be using symbolic links.

sudo ln -s /sw/include/gsl /usr/include/
sudo ln -s /sw/lib/libgsl* /usr/lib

Now attempting a build…

./configure --x-libraries=/usr/X11/lib/ --x-includes=/usrX11/include

Gets you past the GSL issue.

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
…
checking for IceConnectionNumber in -lICE... yes
checking for main in -lX11... yes
checking for main in -lgslcblas... yes
checking for main in -lgsl... yes
checking for XShmCreateImage in -lXext... yes
checking for main in -lXt... yes
checking for main in -lXm... no
NAMOT requires Motif...try LessTif(http://www.lesstif.org)

3b. LessTif

The LessTif symbolic links work the same as the GSL symbolic links. This fink install may take a while.

fink install lesstif

Output below…

Information about 12051 packages read in 1 seconds.
The package 'lesstif' will be built and installed.
Reading build dependency for lesstif-0.95.2-4...
Reading dependency for lesstif-0.95.2-4...
Reading runtime dependency for lesstif-0.95.2-4...
...
Setting up lesstif (0.95.2-4) ...
Clearing dependency_libs of .la files being installed

Updating the list of locally available binary packages.
Scanning dists/stable/main/binary-darwin-i386
New package: dists/stable/main/binary-darwin-i386/x11/app-defaults_20010814-12_darwin-i386.deb
New package: dists/stable/main/binary-darwin-i386/x11/lesstif-bin_0.95.2-4_darwin-i386.deb
New package: dists/stable/main/binary-darwin-i386/x11/lesstif-shlibs_0.95.2-4_darwin-i386.deb
New package: dists/stable/main/binary-darwin-i386/x11/lesstif_0.95.2-4_darwin-i386.deb
./configure --x-libraries=/usr/X11/lib/ --x-includes=/usrX11/include/

But, unfortunately, the LessTif libraries are not in the expected locations.

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
...
checking for IceConnectionNumber in -lICE... yes
checking for main in -lX11... yes
checking for main in -lgslcblas... yes
checking for main in -lgsl... yes
checking for XShmCreateImage in -lXext... yes
checking for main in -lXt... yes
checking for main in -lXm... no
NAMOT requires Motif...try LessTif(http://www.lesstif.org)

So we add the symbolic links…

sudo ln -s /sw/lib/libXm.* /usr/lib
sudo ln -s /sw/include/Xm /usr/include

Which, finally, runs configure…

./configure --x-libraries=/usr/X11/lib/ --x-includes=/usrX11/include/

…with no errors.

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
...
config.status: creating docs/demos/curve/Makefile
config.status: creating docs/demos/dit/Makefile
config.status: creating docs/demos/Makefile
config.status: creating config.h
config.status: executing depfiles commands

NOTE: The make step with Python 2.6 produces the following error below. I did not diagnose this beyond the failure to build under 10.6. OSX 10.8 comes with Python 2.7, which did not produce this problem (I’m assuming this is the origin of the problem).

make

…will produce the following error at the pngwriter.c step.

/bin/sh ../libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I..    -DLIB_HOME="\"/usr/local/share/namot\"" -DHELP_FILE_DIR="\"/usr/local/share/namot\"" -I/System/Library/Frameworks/Python.framework/Versions/2.6/include/python2.6 -I/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/config -g -O2 -c -o _pynamot_la-pngwriter.lo `test -f 'pngwriter.c' || echo './'`pngwriter.c
gcc -DHAVE_CONFIG_H -I. -I. -I.. -DLIB_HOME=\"/usr/local/share/namot\" -DHELP_FILE_DIR=\"/usr/local/share/namot\" -I/System/Library/Frameworks/Python.framework/Versions/2.6/include/python2.6 -I/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/config -g -O2 -c pngwriter.c -MT _pynamot_la-pngwriter.lo -MD -MP -MF .deps/_pynamot_la-pngwriter.TPlo  -fno-common -DPIC -o _pynamot_la-pngwriter.lo
pngwriter.c: In function 'dump_PNG':
pngwriter.c:28: error: 'png_structp' undeclared (first use in this function)
pngwriter.c:28: error: (Each undeclared identifier is reported only once
pngwriter.c:28: error: for each function it appears in.)
pngwriter.c:28: error: expected ';' before 'png_ptr'
pngwriter.c:29: error: 'png_infop' undeclared (first use in this function)
pngwriter.c:29: error: expected ';' before 'info_ptr'
pngwriter.c:30: error: 'png_byte' undeclared (first use in this function)
pngwriter.c:30: error: 'row_pointers' undeclared (first use in this function)
pngwriter.c:30: error: expected expression before ')' token
pngwriter.c:31: error: 'png_text' undeclared (first use in this function)
pngwriter.c:31: error: expected ';' before 'text_ptr'
pngwriter.c:39: warning: incompatible implicit declaration of built-in function 'memset'
pngwriter.c:39: error: 'text_ptr' undeclared (first use in this function)
pngwriter.c:47: error: 'png_ptr' undeclared (first use in this function)
pngwriter.c:47: error: 'PNG_LIBPNG_VER_STRING' undeclared (first use in this function)
pngwriter.c:48: error: 'png_voidp' undeclared (first use in this function)
pngwriter.c:57: error: 'info_ptr' undeclared (first use in this function)
pngwriter.c:60: error: 'png_infopp' undeclared (first use in this function)
pngwriter.c:82: error: 'PNG_COLOR_TYPE_RGB' undeclared (first use in this function)
pngwriter.c:82: error: 'PNG_INTERLACE_ADAM7' undeclared (first use in this function)
pngwriter.c:83: error: 'PNG_COMPRESSION_TYPE_DEFAULT' undeclared (first use in this function)
pngwriter.c:83: error: 'PNG_FILTER_TYPE_DEFAULT' undeclared (first use in this function)
pngwriter.c:85: error: 'PNG_sRGB_INTENT_ABSOLUTE' undeclared (first use in this function)
pngwriter.c:90: error: 'PNG_TEXT_COMPRESSION_NONE' undeclared (first use in this function)
pngwriter.c:93: error: 'PNG_TEXT_COMPRESSION_zTXt' undeclared (first use in this function)
pngwriter.c:104: error: expected expression before ')' token
make[2]: *** [_pynamot_la-pngwriter.lo] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

The build on 10.8 continues as below, with a few warnings about the symbolic link usage that do not seem to affect the program usability (or continued build).

make

Results below…

make  all-recursive
Making all in src
source='namot_wrap.c' object='_pynamot_la-namot_wrap.lo' libtool=yes \
	depfile='.deps/_pynamot_la-namot_wrap.Plo' tmpdepfile='.deps/_pynamot_la-namot_wrap.TPlo' \
	depmode=gcc3 /bin/sh ../depcomp \
	/bin/sh ../libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I..    -DLIB_HOME="\"/usr/local/share/namot\"" -DHELP_FILE_DIR="\"/usr/local/share/namot\"" -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/config -g -O2 -c -o _pynamot_la-namot_wrap.lo `test -f 'namot_wrap.c' || echo './'`namot_wrap.c

...

*** Warning: linker path does not have real file for library -lXm.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libXm and none of the candidates passed a file format test
*** using a file magic. Last file checked: /sw/lib/libXm.la

*** Warning: linker path does not have real file for library -lgsl.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libgsl and none of the candidates passed a file format test
*** using a file magic. Last file checked: /sw/lib/libgsl.la

*** Warning: linker path does not have real file for library -lgslcblas.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libgslcblas and none of the candidates passed a file format test
*** using a file magic. Last file checked: /sw/lib/libgslcblas.la

*** Warning: libtool could not satisfy all declared inter-library
*** dependencies of module _pynamot.  Therefore, libtool will create
*** a static module, that should work as long as the dlopening
*** application is linked with the -dlopen flag.

...

Making all in libs
make[2]: Nothing to be done for `all'.
Making all in docs
Making all in helpfiles
make[3]: Nothing to be done for `all'.
Making all in demos
Making all in 6way
make[4]: Nothing to be done for `all'.
Making all in bending
make[4]: Nothing to be done for `all'.
Making all in cube
make[4]: Nothing to be done for `all'.
Making all in curve
make[4]: Nothing to be done for `all'.
Making all in dit
make[4]: Nothing to be done for `all'.
make[4]: Nothing to be done for `all-am'.
make[3]: Nothing to be done for `all-am'.
Making all in etc
make[2]: Nothing to be done for `all'.

Finally, the install…

make install

Which produces the following:

Making install in src
/bin/sh ../mkinstalldirs /usr/local/lib
 /bin/sh ../libtool --mode=install /usr/bin/install -c  _pynamot.la /usr/local/lib/_pynamot.la
/usr/bin/install -c .libs/_pynamot.lai /usr/local/lib/_pynamot.la
/usr/bin/install -c .libs/_pynamot.a /usr/local/lib/_pynamot.a
ranlib /usr/local/lib/_pynamot.a
chmod 644 /usr/local/lib/_pynamot.a
----------------------------------------------------------------------
Libraries have been installed in:
   /usr/local/lib

If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR'
flag during linking and do at least one of the following:
   - add LIBDIR to the `DYLD_LIBRARY_PATH' environment variable
     during execution

See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
...
/bin/sh ../mkinstalldirs /usr/local/share/namot
 /usr/bin/install -c -m 644 Namot2.512 /usr/local/share/namot/Namot2.512
 /usr/bin/install -c -m 644 Namot2.600 /usr/local/share/namot/Namot2.600
 /usr/bin/install -c -m 644 Namot2.700 /usr/local/share/namot/Namot2.700
 /usr/bin/install -c -m 644 icon1.xv /usr/local/share/namot/icon1.xv
make[2]: Nothing to be done for `install-exec-am'.
make[2]: Nothing to be done for `install-data-am'.

With luck, your launching of NAMOT will open XQuartz and produce a fully operational NAMOT session.

namot

And, for more assistance with producing DNA files for GROMACS, consider the Modifications To The ffG53a6.rtp And ffG53a5.rtp Residue Topology Files Required For Using GROMOS96-NAMOT-GROMACS v1, sed-Based Script For Converting NAMOT And NAMOT2 DNA Output To GROMOS96 Format For GROMACS Topology Generation v1, and sed-Based Script For Converting NAMOT And NAMOT2 DNA Output To ffAMBER Format For GROMACS Topology Generation v1 pages on this blog.

The Low-/Room-temperature Forms Of The Lithiated Salt Of 3,6-dihydroxy-2,5-dimethoxy-p-benzoquinone: A Combined Experimental And Dispersion-Corrected Density Functional Study

Wednesday, November 21st, 2012

In press, in CrystEngComm (DOI:10.1039/C2CE26523). This is my first full paper completely internet-powered, in that I’ve not physically met any of the other co-authors (also in the internet-powered context, the recent paper on [18]-annulene was written and submitted without sharing a room with Dr. Bruce Hudson, but we’re in the same building, so it doesn’t quite count). Also, one of the few papers for which I had no image generation duties (a rare treat).

The discussion of the very interesting possibilities of molecular redox materials in lithium-ion batteries aside, this paper presents a very thorough example of the power of computational approaches to greatly improve the understanding of solid-state molecular materials by (specifically) 1: overcoming the hydrogen position identification problems inherent in X-ray diffraction methods, 2: reproducing the changes that come with temperature variations in molecular crystals and explaining the origins of those (possibly subtle) changes by way of dispersion-corrected density functional theory, and 3: demonstrating that the nature of intermolecular interactions (specifically hydrogen bonding) can be rigorously cataloged across varied materials using post-optimization tools (in this case, using Carlo Gatti’s excellent TOPOND program).

2013dec20_crysengcommcover

Caption: Issue cover.

Gaëtan Bonnard, Anne-Lise Barrès, Olivier Mentré, Damian G. Allis, Carlo Gatti, Philippe Poizot and Christine Frayret*

Abstract

Following our first experimental and computational study of the room temperature (RT) form of the tetrahydrated 3,6-dihydroxy-2,5-dimethoxy-p-benzoquinone (LiM2DHDMQ⋅4H2O) compound, we have researched the occurrence of hydrogen ordering in a new polymorph at lower temperature. The study of polymorphism for the Li2DHDMQ⋅4H2O phase employs both experimental (single crystal X-ray diffraction) and theoretical approaches. While clues for disorder over one bridging water molecule were observed at RT (beta-form),a fully ordered model within a supercell has been evidenced at 100K (alpha-form) and is discussed in conjunction with the features characterizing the first polymorphic form reported previously. Density functional theory (DFT) calculations augmented with an empirical dispersion correction (DFT-D) were applied for the prediction of the structural and chemical bonding properties of the alpha and beta polymorphs of Li2DHDMQ·4H2O. The relative stability of the two polymorphic systems is evidenced. An insight into the interplay of hydrogen bonding, electrostatic and van der Waals (vdW) interactions in affecting the properties of the two polymorphs is gained. This study also shows how information from DFT-D calculations can be used to augment the information from the experimental crystal diffraction pattern and can so play an active role in crystal structure determination, especially by increasing the reliability and accuracy of H-positioning. These more accurate hydrogen coordinates allowed for a quantification of H-bonding strength through a topological analysis of the electron density (Atoms-in-molecules theory).

UNAFold 3.8, MFold Utilities 4.5/4.6 And Additional Component Installation (Using XCode Tools 3 And Fink 0.29.21) For OSX 10.6.x

Wednesday, June 8th, 2011

NOTE: The version numbers for everything are given specifically because aspects of the installation process may change with different versions and, in the event, I will not necessarily know the answer to subsequent problems if major version changes include major changes to the below (and that should clear up the “qualifications” section).

The UNAFold (UNified Nucleic Acid Fold(ing)) nucleic acid folding and hybridization prediction program set (here using version 3.8) can by itself be built with few (and not important) errors in OSX with Xcode Tools 3. The actual running of UNAFold.pl produces several errors that do not affect the run but do affect the amount/format of the output. It is my assumption that any OS running a less-than “kitchen sink” installation of Linux/Unix (Ubuntu, gentoo and Damn Small Linux come to mind) will have these errors and will require subsequent installations of programs/libraries that pieces of UNAFold rely on for processing output into, specifically, images and PDF files. OSX has the same issue that is easy to handle using Fink (and less so trying to install otherwise completely unrelated programs to make these “dependencies” (programs and libraries) available to UNAFold). Once Fink is installed, it is a few-step process to build UNAFold, move the Mfold Utilities contents to their proper folders (and there is a small trick here as well), and generate a UNAFold-complete install for all your DNA/RNA needs.

1. UNAFold 3.8 Installation

To begin, download (currently at mfold.rna.albany.edu/?q=DINAMelt/software), extract, open a terminal, cd into the unafold_3.8 directory (likely ~/Downloads/unafold_3.8), and run ./configure.

[prompt]$ cd ~/Downloads/unafold_3.8
[prompt]$ ./configure

On my machine (MacBook Pro, 10.6.x OSX + XCode Tools 3), this produces the output found in the local file 2011june_unafold_configure_output.txt.

You will likely note two sets of errors in the ./configure output:

./configure: line 8579: sort: No such file or directory
./configure: line 8576: sed: No such file or directory
./configure: line 10077: sort: No such file or directory
./configure: line 10074: sed: No such file or directory

The 10077 and 10074 errors are a bit odd because there are only 10039 lines in the configure file.

Are these errors important? No, you can build UNAFold just fine. I have run into these two “sort” and “sed” problems with a few other build attempts in OSX but have no good answer as to how to get around them (in case you’re wondering, sort and sed are most certainly installed on the machine. The “sort” error can be removed by specifying the path explicitly in the configure file (in line 8579, change “sort” the “/usr/bin/sort”), but the sed error persists in the few attempts I tried to work around it. It doesn’t appear to be a simple PATH issue. I’m not yet interested enough in finding a proper solution but, if you know, please post a comment or send a message. Is it just a character issue as discussed at itmercenary.livejournal.com/1585.html?).

running “make” produces the output found in the local file 2011june_unafold_make_output.txt.

[prompt]$ make

No issues. To install UNAFold, which will default to putting components into /usr/local/bin and /usr/local/share/, run sudo make install, which produces the output found in the local file 2011june_unafold_sudo_make_install_output.txt.

[prompt]$ sudo make install

Again, no issues. You will now have a populated /usr/local/bin folder.

2. MFold Utilities 4.5 (and, currently, the source for 4.6)

The next (optional) step is the inclusion of the mfold_util-4.5-Mac binaries (currently available at mfold.rna.albany.edu/?q=mfold/download-mfold), which I’ve also placed into the /usr/local/bin folder by extracting the contents of this file, them performing a cp * /usr/local/bin from within the MacBin directory.

[prompt]$ cd ~/Downloads/MacBin/
[prompt]$ sudo cp * /usr/local/bin

The processing of the data into plots with these programs requires that a set of *.col files be placed in the folder /usr/local/shared/mfold_util. Furthermore, these *.col are NOT provided in the mfold_util-4.5-Mac binary package. To get these files, you need only download the mfold_util-4.6.tar.gz file (currently at mfold.rna.albany.edu/?q=mfold/download-mfold), cd your way into src, make the /usr/local/shared/mfold_util folder, and copy the *.col files to /usr/local/shared/mfold_util.

[prompt]$ sudo mkdir /usr/local/shared/mfold_util
[prompt]$ cd Downloads/mfold_util-4.6/src
[prompt]$ sudo cp *.col /usr/local/shared/mfold_util

3. Fink 0.29.21 Install From Scratch

The first indication that other work was required came from trying to run mutplot randomly, which produced the following error:

dyld: Library not loaded: /sw/lib/libpng12.0.dylib
  Referenced from: /usr/local/bin/mutplot
  Reason: image not found
Trace/BPT trap

As digging around for libraries is not as straightforward as it would be for a Linux distro, I chose instead to solve the many problems by installing dependencies through the Fink program (currently fink-0.29.21). As 10.6.x users will find that there is no available Fink binary, you must build this from the source (which, with Xcode Tools 3 installed, occurs without error. If you don’t have Xcode Tools 3 installed, the new mechanism for buying a copy of XCode Tools 4 is less than ideal (to me, anyway. $4.99?) but now occurs through the App Store).

Download the fink source (fink 0.29.21), extract, cd into the fink-0.29.21 directory, and run bootstrap. Upon completion, you run pathsetup.sh, source your .profile, and update fink.

[prompt]$ cd ~/Downloads/fink-0.29.21
[prompt]$ ./bootstrap
[prompt]$ . /sw/bin/pathsetup.sh 
[prompt]$ cd ~/
[prompt]$ source .profile
[prompt]$ fink selfupdate-rsync
[prompt]$ fink update-all

The output for my installation can be found in 2011june_fink_install_output.txt. The rsync output can be found in 2011june_fink_selfupdate_rsync_output.txt. NOTE: You will be asked several questions about the installation process. Be prepared to blindly select the default settings with [enter], but don’t just walk away from the screen.

This completes the UNAFold install, MacBin install, and Fink install, meaning now we can walk through the dependencies.

4. Installing UNAFold (well, MFold Utils) Dependencies

First dependency-free UNAFold.pl run attempt produces the following error:

[prompt]$ UNAFold.pl seqtest.txt 
Checking for boxplot_ng... dyld: Library not loaded: /sw/lib/libpng12.0.dylib
  Referenced from: /usr/local/bin/boxplot_ng
  Reason: image not found
found, supports Postscript
Checking for hybrid-plot-ng... found, supports Postscript
Checking for sir_graph_ng or sir_graph... dyld: Library not loaded: /sw/lib/libpng12.0.dylib
  Referenced from: /usr/local/bin/sir_graph
  Reason: image not found
found, supports Postscript
Checking for ps2pdfwr... not found
Calculating for seqtest.txt, t = 37

As the UNAFold install page states, you need glut, the GD library, and gnuplot installed (and all of the many libraries therein).

[prompt]$ fink install libjpeg tetex gd2 gnuplot

For gnuplot, you will be required to make a few selections during the build process (blindly hitting the enter key at these questions will do, but this is not just a “type and go” install process. And it took about two hours on a MBP).

A final working error-free run looks as below, leaving you to process the data with the MFold Utilities as you like:

[prompt]$ UNAFold.pl seqtest.txt 
Checking for boxplot_ng... found, supports Postscript
Checking for hybrid-plot-ng... found, supports Postscript
Checking for sir_graph_ng or sir_graph... found, supports Postscript
Checking for ps2pdfwr... found
Calculating for seqtest.txt, t = 37

Terahertz Spectroscopic Investigation Of S-(+)-Ketamine Hydrochloride And Vibrational Assignment By Density Functional Theory, “Function Follows Functional Follows Formalism”

Sunday, February 21st, 2010

Accepted in the Journal of Physical Chemistry A, with my fingers crossed for pulling off the rare double-header in an upcoming print edition of the journal (having missed it by three intermediate articles with the Cs2B12H12 and HMX papers back in 2006 (you’d keep track, too). A fortuitous overlap of scheduled defense dates between P. Hakey, Ph.D. and M. Hudson, A.B.D.). A brief summary of interesting points from this study is provided below, including what I think is a useful point about how to most easily interpret AND represent solid-state vibrational spectra for publications.

1. AS USUAL, YOU CANNOT USE GAS-PHASE CALCULATIONS TO ASSIGN SOLID-STATE TERAHERTZ SPECTRA. It will take a phenomenal piece of data and one helluvan interpretation to convince me otherwise. As a more subtle point (for those attempting an even worse job of vibrational mode assignment), if the molecule exists in its protonated form in the solid-state, do not use the neutral form for your gas-phase calculation (this is a point that came up as part of an MDMA re-assignment published (and posted here) previously).

2. It is very difficult to find what I would consider to be “complete data sets” for molecules and solids being studied by spectroscopic and computational methods. For many molecular solids, the influences of thermal motion are not important to providing a proper vibrational analysis by solid-state density functional theory methods. Heating a crystal may make spectral lines broader, but phase changes and unusual spectral features do not often result when heating a sample from cryogenic (say, liquid nitrogen) to room temperature. Yes, there are thousands of cases where this is not true, but several fold more cases where it is. We are fortunate to live in a temperature regime where characterization is reasonably straightforward and yet we can modify a system to observe its subtle changes under standard laboratory conditions. The THz spectrum of S-(+)-Ketamine Hydrochloride gets a bit cleaner upon cooling, which makes the assignment easier. As the ultimate goal is to be able to characterize these systems in a person’s pocket instead of their liquid nitrogen thermos, the limited observed change to the spectrum upon cooling is important to note.

3. Crystal06 vs. DMol3 – This paper contains what is hoped to be a level, pragmatic discussion about the strengths and weaknesses of computational tools available to terahertz spectroscopists for use in their efforts to assign spectra. This type of discussion is, as a computational chemist using tools and not developing tools, a touchy subject to present on not because of the finger-pointing of limitations with software, but because the Crystal06 team and Accelrys (through Delley’s initial DMol3 code) clearly are doing things that the vast majority of their users (myself included) could in no way do by themselves. The analysis for the theory-minded terahertz spectroscopist is presented comparing two metrics – speed and functionality (specifically, infra-red intensity prediction). What is observed as the baseline is that both DMol3 and Crystal06 make available density functionals and basis sets that, when used at high levels of theory and rigorous convergence criteria, produce simulated terahertz spectra with vibrational mode energies that are in good (if not very good) agreement with each other. For the terahertz spectroscopist, Crystal06 provides as output (although this is system size- and basis set size-dependent) rigorous infrared intensity predictions for vibrational modes, inseparable from mode energy as “the most important” pieces of information for mode assignments. While DMol3 does not produce infrared intensities (the many previous terahertz papers I’ve worked on employed difference-dipole calculations that are, at best, a guesstimate), DMol3 produces very good mode energy predictions in 1/6th to (I’ve seen it happen) 1/10th the time of a comparable Crystal06 calculation. This is the reason DMol3 has been the go-to program for all of the neutron scattering spectroscopy papers cited on this blog (where intensity is determined by normal mode eigenvectors, which are provided by both (and any self-respecting quantum chemical code) programs).

Now, it should be noted that this difference in functionality has NOTHING to do with formalism. Both codes are excellent for what they are intended to do. To the general assignment-minded spectroscopist (the target audience of the Discussion in the paper), any major problem with Crystal06 likely originates with the time to run calculations (and, quite frankly, the time it takes to run a calculation is the worst possible reason for not running a calculation if you need that data. Don’t blame the theory, blame the deadline). In my past exchanges with George Fitzgerald of Accelrys, the issue of DMol3 infrared intensities came up as a feature request that would greatly improve the (this) user experience and Dr. Fitzgerald is very interested (of course) in making a great code that much better. Neither code will be disappearing from my toolbox anytime soon.

4. The Periodicity Of The Molecular Solid Doesn’t Care What The Space Group Is – One of the more significant problems facing the assignment-minded spectroscopist is the physical description of molecular motion in a vibrational mode. In the simplest motions involving the most weakly interacting molecules, translational and rotational motions are often quite easy to pick out and state as such. When the molecules are very weakly interacting, often the intramolecular vibrational modes are easy to identify as well, as they are largely unchanged from their gas-phase descriptions. In ionic solids or strongly hydrogen-bonded systems, it is often much harder to separate out individual molecular motions from “group modes” involving the in- and out-of-phase motions of multiple molecules. In the unit cells of molecular solids, it can be the case that these group modes appear, by inspection, to be extremely complicated, sometimes too involved to easily describe in the confines of a table in a journal article.

S-(+)-Ketamine Hydrochloride is one such example where a great simplification in vibrational mode description comes from thinking, well, “outside the box.” The image below shows two cells and the surrounding molecules of S-(+)-Ketamine Hydrochloride. As it is difficult to see why the mode descriptions are complex from just an image, assume that I am right in this statement of complexity. Part of this complexity comes from the fact that the two molecules in the unit cell are not strongly interacting, instead packed together by van der Waals and dispersion forces more than anything else. The key to a greatly simplified assignment comes from the realization that the most polar fragments of these molecules are aligned on the edges of the unit cell.

An alternate view of molecular vibrational motion comes from considering not the contents of the defined unit cell but the hydrogen-bonding and ionic bonding arrangement that exists between pairs of molecules between unit cells. The colorized image below shows two distinct chains (red and blue) that, when the predicted vibrational modes are animated, become trivial to characterize as the relative motions of a hydrogen/ionic-bonded chain. Rotational motions appear as spinning motions of the chains, translational motions as either chain sliding motions or chain breathing modes. It appears as a larger macromolecule undergoing very “molecular” vibrations. In optical vibrational spectroscopy, selection rules and the unit cell arrangement do not produce in- and out-of-phase motions of the red and blue chains, as only one “chain” exists in the periodicity of the unit cell. In neutron scattering spectroscopy, these relative motions between red and blue would appear in the phonon region. This same discussion was had, in part, in a previous post on the solid-state terahertz assignment of ephedrine (with a nicer picture).

So, look at the cell contents, then see if there’s more structure than crystal packing would indicate. It greatly simplifies the assignment (which, in turn. greatly simplifies the reader’s digestion of the vibrational motions).

Patrick M. Hakey, Damian G. Allis, Matthew R. Hudson, Wayne Ouellette, and Timothy M. Korter

Department of Chemistry, Syracuse University, Syracuse, New York 13244-4100

Abstract: The terahertz (THz) spectrum of (S)-(+)-ketamine hydrochloride has been investigated from 10 to 100 cm-1 (0.3-3.0 THz) at both liquid-nitrogen (78 K) and room (294 K) temperatures. Complete solid-state density functional theory structural analyses and normal-mode analyses are performed using a single hybrid density functional (B3LYP) and three generalized gradient approximation density functionals (BLYP, PBE, PW91). An assignment of the eight features present in the well-resolved cryogenic spectrum is provided based upon solid-state predictions at a PW91/6-31G(d,p) level of theory. The simulations predict that a total of 13 infrared- active vibrational modes contribute to the THz spectrum with 26.4% of the spectral intensity originating from external lattice vibrations.

pubs.acs.org/journal/jpcafh
www.somewhereville.com/?p=29
www.somewhereville.com/?p=26
www.somewhereville.com/?p=126
en.wikipedia.org/wiki/Density_functional_theory
en.wikipedia.org/wiki/Ketamine
www.crystal.unito.it
accelrys.com/products/materials-studio/quantum-and-catalysis-software.html
en.wikipedia.org/wiki/Time_domain_terahertz_spectroscopy
en.wikipedia.org/wiki/Computational_chemistry
accelrys.com
en.wikipedia.org/wiki/Inelastic_neutron_scattering
en.wikipedia.org/wiki/Vibrational_spectroscopy
www.somewhereville.com/?p=680

Obligatory

  • CNYO

  • Sol. Sys. Amb.

  • Ubuntu 4 Nano

  • NMT Review

  • N-Fact. Collab.

  • Pres. Asn. CNY

  • T R P Nanosys

  • Nano Gallery

  • nano gallery
  • Aerial Photos

    More @ flickr.com

    Syracuse Scenes

    More @ flickr.com