Dipole Derivative, Polarizability Derivative, And Vibrational Polarizability Contribution Output From Gaussian09 With IOp(7/33)

For those itching for polarizability derivative orientation information and wondering where it is when you ask for it… what's included below is a combination of a few points in one, specifically pointing out that the IOp options are not just "another part" of the Gaussian input file (with the IOp Overlays currently linked HERE).

The problem I realized after an email from Gaussian HQ was that, as was the case for the KMLYP density functional call discussed in previous posts about [18]-annulene, "opt" and "freq" keyword combinations are seen as two distinct runs in Gaussian that don't pass the IOp information along (and, admittedly, I should have remembered that). Specifically, the additional print-out for the polarizability info is called by IOp(7/33=3).

What I provide below is a two-in-one input file that saves you from having to run double-duty input files in the checkpoint file. This also serves as a template for those looking for examples of combining multi-step input files that include mixed basis sets (as many of the problems I've been emailed stem from carriage return issues more than anything else). Note that the input file is set to run Raman intensities and produce higher-precision (hpmodes) eigenvectors (so, if you just want to test this, remove the "raman").

#p scf=tight opt=tight b3lyp/GEN pseudo=read

C4H5Cl_B3LYP_631Gdp_LanL2DZ_IR_Raman Opt

0 1
 C                 -1.74671095   -0.64168298    0.00000000
 H                 -1.53944096   -1.69141587    0.00000000
 C                 -0.73010315    0.25446188    0.00000000
 H                 -0.93737314    1.30419477    0.00000000
 C                  0.73010315   -0.25446188    0.00000000
 H                  0.93737314   -1.30419477    0.00000000
 C                  1.74671095    0.64168298    0.00000000
 H                  1.53944096    1.69141587    0.00000000
 H                 -3.73526840    0.03531673    0.00000000
 Cl                 3.73526840   -0.03531673    0.00000000

C H 0


#p Geom=Check Guess=Read freq(raman,hpmodes) iop(7/33=3)
C4H5Cl_B3LYP_631Gdp_LanL2DZ_IR_Raman Freq
0 1

Note the carriage return after the second "0 1".

For the demo molecule above, additional print-out below.

 Dipole derivatives wrt mode   1:  3.96988D-14 -1.15747D-14 -1.96904D-01
 Polarizability derivatives wrt mode          1
                 1             2             3 
      1   0.000000D+00  0.000000D+00  0.206435D+00
      2   0.000000D+00  0.000000D+00  0.143916D-01
      3   0.206435D+00  0.143916D-01  0.000000D+00
 Vibrational polarizability contributions from mode   1       0.0000000       0.0000000       0.0257731
 IFr=  0 A012= 0.23D-23 0.77D+00 0.13D+00 Act= 0.90D+00 DepolP= 0.75D+00 DepolU= 0.86D+00

Alternately, keep track of the checkpoint file.

Bond Alternation In Infinite Periodic Polyacetylene: Dynamical Treatment Of The Anharmonic Potential

In press (DOI:10.1016/j.molstruc.2012.07.051) in the Journal Of Molecular Structure. May go down in history as a hardest-fought paper acceptance. In a similar line of research as the [18]-annulene study, but exploring the infinite limit of geometry and bond length alternation energy barrier for this infinite case. If the numbers are correct, the infinite polyene chains (polyacetylene) do not exhibit bond length alternation because the Peierls' barrier between the single-double and double-single bond alternate minima is below the vibrational zero-point level. Plenty of ramifications.

Bruce S. Hudson and Damian G. Allis

Abstract. The potential energy of the infinite periodic chain model of polyacetylene (pPA) is symmetric with two equivalent minima separated by the Peierls' stabilization barrier. In this work it is shown how an energy scale and vibrational energy levels for this highly anharmonic Peierls' degree of freedom can be estimated. Attention is given to the potential energy increase for large deformations. The Born-Karman treatment of translational symmetry is applied. Two empirical methods and a direct periodic boundary condition (PBC) density functional theory (DFT) calculations are in semi-quantitative agreement, each leading to the conclusion that pPA has a zero-point level that is above the Peierls' barrier. The argument does not depend critically on the barrier height or the other parameters of the model or the computation method. It is concluded that pPA will not exhibit bond alternation and that the zero-point average geometry does not preclude possible conductivity.