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All results from a given calculation for C6H4O2 (parabenzoquinone)

using model chemistry: MP2/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D2H 1Ag
Energy calculated at MP2/3-21G*
 hartrees
Energy at 0K-377.866426
Energy at 298.15K-377.870924
Nuclear repulsion energy318.107334
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP2/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Ag 3230 3072 0.00      
2 Ag 1652 1571 0.00      
3 Ag 1544 1469 0.00      
4 Ag 1217 1157 0.00      
5 Ag 745 709 0.00      
6 Ag 459 437 0.00      
7 Au 1035 985 0.00      
8 Au 367 349 0.00      
9 B1g 787 749 0.00      
10 B1u 3207 3051 1.50      
11 B1u 1588 1511 40.94      
12 B1u 1407 1339 7.38      
13 B1u 949 903 6.26      
14 B1u 732 697 0.06      
15 B2g 1028 978 0.00      
16 B2g 810 771 0.00      
17 B2g 268 255 0.00      
18 B2u 3227 3070 7.78      
19 B2u 1607 1529 13.27      
20 B2u 1315 1251 39.32      
21 B2u 1072 1019 87.24      
22 B2u 387 368 18.31      
23 B3g 3207 3051 0.00      
24 B3g 1407 1338 0.00      
25 B3g 1221 1162 0.00      
26 B3g 600 570 0.00      
27 B3g 455 433 0.00      
28 B3u 934 889 98.77      
29 B3u 525 499 11.06      
30 B3u 99 94 8.90      

Unscaled Zero Point Vibrational Energy (zpe) 18540.2 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 17637.3 cm-1
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.
Rotational Constants (cm-1) from geometry optimized at MP2/3-21G*
ABC
0.17519 0.05292 0.04064

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/3-21G*

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.468
C2 0.000 0.000 -1.468
C3 0.000 1.266 0.676
C4 0.000 -1.266 0.676
C5 0.000 -1.266 -0.676
C6 0.000 1.266 -0.676
O7 0.000 0.000 2.731
O8 0.000 0.000 -2.731
H9 0.000 2.188 1.250
H10 0.000 -2.188 1.250
H11 0.000 -2.188 -1.250
H12 0.000 2.188 -1.250

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 O7 O8 H9 H10 H11 H12
C12.93591.49331.49332.48972.48971.26314.19902.19892.19893.48903.4890
C22.93592.48972.48971.49331.49334.19901.26313.48903.48902.19892.1989
C31.49332.48972.53192.87011.35182.41383.63451.08613.50133.95452.1350
C41.49332.48972.53191.35182.87012.41383.63453.50131.08612.13503.9545
C52.48971.49332.87011.35182.53193.63452.41383.95452.13501.08613.5013
C62.48971.49331.35182.87012.53193.63452.41382.13503.95453.50131.0861
O71.26314.19902.41382.41383.63453.63455.46212.64242.64244.54244.5424
O84.19901.26313.63453.63452.41382.41385.46214.54244.54242.64242.6424
H92.19893.48901.08613.50133.95452.13502.64244.54244.37615.03962.4993
H102.19893.48903.50131.08612.13503.95452.64244.54244.37612.49935.0396
H113.48902.19893.95452.13501.08613.50134.54242.64245.03962.49934.3761
H123.48902.19892.13503.95453.50131.08614.54242.64242.49935.03964.3761

picture of parabenzoquinone state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C3 C6 122.034 C1 C3 H9 116.076
C1 C4 C5 122.034 C1 C4 H10 116.076
C2 C5 C4 122.034 C2 C5 H11 116.076
C2 C6 C3 122.034 C2 C6 H12 116.076
C3 C1 C4 115.933 C3 C1 O7 122.034
C3 C6 H12 121.891 C4 C1 O7 122.034
C4 C5 H11 121.891 C5 C2 C6 115.933
C5 C2 O8 122.034 C5 C4 H10 121.891
C6 C2 O8 122.034 C6 C3 H9 121.891
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability