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All results from a given calculation for C6H4O2 (parabenzoquinone)

using model chemistry: MP2/CEP-121G*

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/CEP-121G*
 hartrees
Energy at 0K-67.735579
Energy at 298.15K 
Nuclear repulsion energy160.614497
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/CEP-121G*
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 3232 3080 0.00      
2 Ag 1672 1593 0.00      
3 Ag 1606 1530 0.00      
4 Ag 1164 1109 0.00      
5 Ag 774 737 0.00      
6 Ag 442 421 0.00      
7 Au 872 831 0.00      
8 Au 269 256 0.00      
9 B1g 727 693 0.00      
10 B1u 3214 3062 0.80      
11 B1u 1658 1580 192.51      
12 B1u 1375 1310 4.75      
13 B1u 942 898 11.88      
14 B1u 747 712 0.05      
15 B2g 888 846 0.00      
16 B2g 520 496 0.00      
17 B2g 317i 302i 0.00      
18 B2u 3231 3078 6.90      
19 B2u 1608 1533 21.59      
20 B2u 1338 1274 74.24      
21 B2u 1087 1035 43.14      
22 B2u 400 381 23.86      
23 B3g 3215 3063 0.00      
24 B3g 1414 1347 0.00      
25 B3g 1243 1185 0.00      
26 B3g 595 567 0.00      
27 B3g 438 417 0.00      
28 B3u 861 820 98.10      
29 B3u 481 459 4.94      
30 B3u 78 75 12.72      

Unscaled Zero Point Vibrational Energy (zpe) 17886.2 cm-1
Scaled (by 0.9528) Zero Point Vibrational Energy (zpe) 17042.0 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/CEP-121G*
ABC
0.17223 0.05411 0.04117

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-121G*

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.450
C2 0.000 0.000 -1.450
C3 0.000 1.278 0.679
C4 0.000 -1.278 0.679
C5 0.000 -1.278 -0.679
C6 0.000 1.278 -0.679
O7 0.000 0.000 2.696
O8 0.000 0.000 -2.696
H9 0.000 2.196 1.264
H10 0.000 -2.196 1.264
H11 0.000 -2.196 -1.264
H12 0.000 2.196 -1.264

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 O7 O8 H9 H10 H11 H12
C12.90061.49271.49272.48402.48401.24554.14612.20412.20413.49163.4916
C22.90062.48402.48401.49271.49274.14611.24553.49163.49162.20412.2041
C31.49272.48402.55662.89531.35892.38743.60931.08833.52333.98112.1494
C41.49272.48402.55661.35892.89532.38743.60933.52331.08832.14943.9811
C52.48401.49272.89531.35892.55663.60932.38743.98112.14941.08833.5233
C62.48401.49271.35892.89532.55663.60932.38742.14943.98113.52331.0883
O71.24554.14612.38742.38743.60933.60935.39172.62172.62174.52814.5281
O84.14611.24553.60933.60932.38742.38745.39174.52814.52812.62172.6217
H92.20413.49161.08833.52333.98112.14942.62174.52814.39245.06802.5281
H102.20413.49163.52331.08832.14943.98112.62174.52814.39242.52815.0680
H113.49162.20413.98112.14941.08833.52334.52812.62175.06802.52814.3924
H123.49162.20412.14943.98113.52331.08834.52812.62172.52815.06804.3924

picture of parabenzoquinone state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C3 C6 121.091 C1 C3 H9 116.417
C1 C4 C5 121.091 C1 C4 H10 116.417
C2 C5 C4 121.091 C2 C5 H11 116.417
C2 C6 C3 121.091 C2 C6 H12 116.417
C3 C1 C4 117.818 C3 C1 O7 121.091
C3 C6 H12 122.492 C4 C1 O7 121.091
C4 C5 H11 122.492 C5 C2 C6 117.818
C5 C2 O8 121.091 C5 C4 H10 122.492
C6 C2 O8 121.091 C6 C3 H9 122.492
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability