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VCD intensities with (apparently) wrong signs

Posted: 30 Mar 2017, 09:18
by tteodoro
Dear experts,

I have run a couple of simple tests to get VCD intensities for HNDT and S-d2-oxirane (outputs attached). These results I compared with ones from DFT calculations on ADF (using the same geometries). Besides some expected shifts due to the different levels of calculation, frequencies and the absolute values of the rotational strengths are okay. But the signs are opposite for virtually all modes (Tables below).

In this paper http://aip.scitation.org/doi/10.1063/1.4960653 one can find MD calculations and experimental data for S-d2-oxirane, which agree with the DFT results. Could this be something I am missing in the Dalton inputs or a possible bug?

Regards,

Tiago


HNDT
BP86/TZP HF/cc-pVTZ
Freq. R.S. Freq. R.S.
828.03 4.78 1032.99 -6.94
1157.22 -9.55 1316.32 12.72
1426.67 4.84 1608.62 -5.95
2101.67 -0.62 2131.86 0.59
2515.49 0.62 2547.33 -0.41
3445.20 -0.13 3488.23 0.06


S-d2-oxirane
BP86/TZP HF/cc-pVTZ
Freq. R.S. Freq. R.S.
645.27 -0.31  766.27 1.02
733.20 7.57   823.36 -12.96
802.84 3.55   829.72 -3.24
867.59 10.87  956.09 0.05
891.58 -3.68 1034.17 0.60
941.69 -28.11 1043.44 28.89
1080.19 7.02 1260.00 -15.34
1090.21 -1.24 1277.21 -7.34
1218.37 11.96 1317.26 1.29
1315.13 -0.59 1485.52 1.65
1379.47 -8.83 1533.97 9.07
2235.78 -20.66 2291.99 15.38
2246.37 16.76 2307.20 -13.51
3049.82 -32.34 3126.88 24.78
3055.53 42.45 3130.40 -31.59