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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-377.870942
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 3083 0.00      
2 Ag 1652 1577 0.00      
3 Ag 1544 1474 0.00      
4 Ag 1217 1161 0.00      
5 Ag 745 711 0.00      
6 Ag 459 438 0.00      
7 Au 1035 988 0.00      
8 Au 367 350 0.00      
9 B1g 787 751 0.00      
10 B1u 3207 3061 1.50      
11 B1u 1588 1516 40.94      
12 B1u 1407 1343 7.38      
13 B1u 949 906 6.26      
14 B1u 732 699 0.06      
15 B2g 1028 981 0.00      
16 B2g 810 773 0.00      
17 B2g 268 256 0.00      
18 B2u 3227 3080 7.78      
19 B2u 1607 1534 13.27      
20 B2u 1315 1256 39.32      
21 B2u 1072 1023 87.24      
22 B2u 387 370 18.31      
23 B3g 3207 3061 0.00      
24 B3g 1407 1343 0.00      
25 B3g 1221 1165 0.00      
26 B3g 600 572 0.00      
27 B3g 455 434 0.00      
28 B3u 934 892 98.77      
29 B3u 525 501 11.06      
30 B3u 99 95 8.90      

Unscaled Zero Point Vibrational Energy (zpe) 18540.2 cm-1
Scaled (by 0.9545) Zero Point Vibrational Energy (zpe) 17696.6 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