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All results from a given calculation for C6H4O2 (parabenzoquinone)

using model chemistry: QCISD/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 QCISD/3-21G*
 hartrees
Energy at 0K-377.902747
Energy at 298.15K-377.907207
Nuclear repulsion energy317.972769
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 QCISD/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 3187 3063 0.00      
2 Ag 1699 1633 0.00      
3 Ag 1618 1555 0.00      
4 Ag 1212 1165 0.00      
5 Ag 730 702 0.00      
6 Ag 457 439 0.00      
7 Au 1034 994 0.00      
8 Au 363 349 0.00      
9 B1g 782 751 0.00      
10 B1u 3164 3041 1.25      
11 B1u 1661 1596 131.25      
12 B1u 1405 1350 3.10      
13 B1u 943 907 8.19      
14 B1u 724 696 0.06      
15 B2g 1028 988 0.00      
16 B2g 803 772 0.00      
17 B2g 265 255 0.00      
18 B2u 3184 3060 9.95      
19 B2u 1637 1573 8.11      
20 B2u 1305 1254 39.03      
21 B2u 1062 1021 86.56      
22 B2u 389 374 19.82      
23 B3g 3164 3041 0.00      
24 B3g 1395 1341 0.00      
25 B3g 1208 1161 0.00      
26 B3g 595 571 0.00      
27 B3g 456 438 0.00      
28 B3u 923 887 99.54      
29 B3u 517 497 8.53      
30 B3u 96 92 9.75      

Unscaled Zero Point Vibrational Energy (zpe) 18502.0 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 17782.3 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 QCISD/3-21G*
ABC
0.17332 0.05309 0.04064

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

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.472
C2 0.000 0.000 -1.472
C3 0.000 1.273 0.674
C4 0.000 -1.273 0.674
C5 0.000 -1.273 -0.674
C6 0.000 1.273 -0.674
O7 0.000 0.000 2.724
O8 0.000 0.000 -2.724
H9 0.000 2.196 1.253
H10 0.000 -2.196 1.253
H11 0.000 -2.196 -1.253
H12 0.000 2.196 -1.253

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 O7 O8 H9 H10 H11 H12
C12.94501.50281.50282.49612.49611.25134.19622.20652.20653.50013.5001
C22.94502.49612.49611.50281.50284.19621.25133.50013.50012.20652.2065
C31.50282.49612.54682.88191.34882.41283.62891.08893.51693.96862.1370
C41.50282.49612.54681.34882.88192.41283.62893.51691.08892.13703.9686
C52.49611.50282.88191.34882.54683.62892.41283.96862.13701.08893.5169
C62.49611.50281.34882.88192.54683.62892.41282.13703.96863.51691.0889
O71.25134.19622.41282.41283.62893.62895.44752.64242.64244.54304.5430
O84.19621.25133.62893.62892.41282.41285.44754.54304.54302.64242.6424
H92.20653.50011.08893.51693.96862.13702.64244.54304.39115.05632.5068
H102.20653.50013.51691.08892.13703.96862.64244.54304.39112.50685.0563
H113.50012.20653.96862.13701.08893.51694.54302.64245.05632.50684.3911
H123.50012.20652.13703.96863.51691.08894.54302.64242.50685.05634.3911

picture of parabenzoquinone state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C3 C6 122.077 C1 C3 H9 115.800
C1 C4 C5 122.077 C1 C4 H10 115.800
C2 C5 C4 122.077 C2 C5 H11 115.800
C2 C6 C3 122.077 C2 C6 H12 115.800
C3 C1 C4 115.847 C3 C1 O7 122.077
C3 C6 H12 122.123 C4 C1 O7 122.077
C4 C5 H11 122.123 C5 C2 C6 115.847
C5 C2 O8 122.077 C5 C4 H10 122.123
C6 C2 O8 122.077 C6 C3 H9 122.123
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability