Compare vibrational frequencies for two calculations
for HCOOHH2O (Formic acid water dimer)
A =
HF/6-31G*
B =
MP2/6-31G*
scale factors=0.8985, 0.943
|
symmetry |
|
frequency (cm-1) |
|
reduced mass (amu) |
|
IR Intensity (km mol-1) |
|
Raman Activity (Å4/u) |
mode number |
A |
B |
|
A |
B |
diff. |
ratio |
|
A |
B |
diff. |
ratio |
|
A |
B |
diff. |
ratio |
|
A |
B |
diff. |
ratio |
1 |
A |
A |
|
3735 |
3634 |
101.2 |
1.028 |
|
1.080 |
1.075 |
0.005 |
1.004 |
|
128.30 |
99.10 |
29.20 |
1.295 |
|
|
|
|
|
2 |
A |
A |
|
3616 |
3457 |
158.7 |
1.046 |
|
1.049 |
1.052 |
-0.003 |
0.997 |
|
104.51 |
158.16 |
-53.65 |
0.661 |
|
|
|
|
|
3 |
A |
A |
|
3436 |
3130 |
305.9 |
1.098 |
|
1.066 |
1.066 |
-0.000 |
1.000 |
|
487.21 |
564.51 |
-77.30 |
0.863 |
|
|
|
|
|
4 |
A |
A |
|
2978 |
2982 |
-3.2 |
0.999 |
|
1.094 |
1.092 |
0.002 |
1.002 |
|
76.45 |
96.65 |
-20.20 |
0.791 |
|
|
|
|
|
5 |
A |
A |
|
1794 |
1705 |
89.3 |
1.052 |
|
6.895 |
5.144 |
1.751 |
1.340 |
|
465.42 |
260.71 |
204.71 |
1.785 |
|
|
|
|
|
6 |
A |
A |
|
1645 |
1644 |
0.6 |
1.000 |
|
1.084 |
1.112 |
-0.028 |
0.975 |
|
143.35 |
141.06 |
2.29 |
1.016 |
|
|
|
|
|
7 |
A |
A |
|
1414 |
1418 |
-4.0 |
0.997 |
|
1.187 |
1.259 |
-0.073 |
0.942 |
|
5.03 |
1.41 |
3.62 |
3.572 |
|
|
|
|
|
8 |
A |
A |
|
1371 |
1348 |
22.7 |
1.017 |
|
1.465 |
1.263 |
0.202 |
1.160 |
|
28.80 |
12.31 |
16.49 |
2.339 |
|
|
|
|
|
9 |
A |
A |
|
1206 |
1181 |
25.2 |
1.021 |
|
3.498 |
4.194 |
-0.696 |
0.834 |
|
281.24 |
218.42 |
62.82 |
1.288 |
|
|
|
|
|
10 |
A |
A |
|
1082 |
1031 |
51.0 |
1.049 |
|
1.592 |
1.358 |
0.234 |
1.172 |
|
0.73 |
26.90 |
-26.18 |
0.027 |
|
|
|
|
|
11 |
A |
A |
|
842 |
925 |
-82.9 |
0.910 |
|
1.143 |
1.270 |
-0.127 |
0.900 |
|
239.51 |
152.03 |
87.48 |
1.575 |
|
|
|
|
|
12 |
A |
A |
|
672 |
682 |
-9.5 |
0.986 |
|
4.159 |
2.340 |
1.819 |
1.777 |
|
66.83 |
162.39 |
-95.56 |
0.412 |
|
|
|
|
|
13 |
A |
A |
|
520 |
617 |
-97.2 |
0.842 |
|
1.124 |
1.460 |
-0.336 |
0.770 |
|
244.33 |
173.89 |
70.44 |
1.405 |
|
|
|
|
|
14 |
A |
A |
|
316 |
360 |
-44.3 |
0.877 |
|
1.223 |
1.236 |
-0.013 |
0.989 |
|
115.18 |
101.10 |
14.08 |
1.139 |
|
|
|
|
|
15 |
A |
A |
|
222 |
286 |
-64.1 |
0.776 |
|
1.202 |
1.136 |
0.067 |
1.059 |
|
77.83 |
80.76 |
-2.93 |
0.964 |
|
|
|
|
|
16 |
A |
A |
|
196 |
236 |
-40.1 |
0.830 |
|
6.550 |
6.411 |
0.139 |
1.022 |
|
29.89 |
41.29 |
-11.40 |
0.724 |
|
|
|
|
|
17 |
A |
A |
|
161 |
190 |
-29.9 |
0.843 |
|
1.675 |
3.289 |
-1.614 |
0.509 |
|
52.74 |
26.46 |
26.28 |
1.993 |
|
|
|
|
|
18 |
A |
A |
|
149 |
185 |
-36.5 |
0.803 |
|
4.265 |
2.242 |
2.023 |
1.902 |
|
7.98 |
7.88 |
0.10 |
1.013 |
|
|
|
|
|
scaled by |
|
|
0.8985 |
0.943 |
19 08 20 15 07
See section III.C.1 List or set vibrational scaling factors
to change the scale factors used here.
See section III.C.2
Calculate a vibrational scaling factor for a given set of molecules
to determine the least squares best scaling factor.