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All results from a given calculation for C8H6 (Pentalene)

using model chemistry: MP2=FULL/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2H 1Ag
Energy calculated at MP2=FULL/3-21G*
 hartrees
Energy at 0K-305.334721
Energy at 298.15K-305.340059
HF Energy-304.618080
Nuclear repulsion energy310.431791
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=FULL/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 3267 3097 0.00      
2 Ag 3244 3075 0.00      
3 Ag 3233 3065 0.00      
4 Ag 1603 1520 0.00      
5 Ag 1521 1442 0.00      
6 Ag 1371 1300 0.00      
7 Ag 1303 1235 0.00      
8 Ag 1173 1112 0.00      
9 Ag 1150 1091 0.00      
10 Ag 900 853 0.00      
11 Ag 834 790 0.00      
12 Ag 749 710 0.00      
13 Ag 646 612 0.00      
14 Au 854 809 7.70      
15 Au 792 750 32.04      
16 Au 687 651 110.15      
17 Au 484 459 2.45      
18 Au 290 275 2.62      
19 Au 100 94 7.63      
20 Bg 870 825 0.00      
21 Bg 817 775 0.00      
22 Bg 709 672 0.00      
23 Bg 612 580 0.00      
24 Bg 531 503 0.00      
25 Bu 3267 3097 23.11      
26 Bu 3244 3075 9.07      
27 Bu 3234 3066 6.76      
28 Bu 1597 1513 10.79      
29 Bu 1490 1413 4.93      
30 Bu 1365 1294 12.44      
31 Bu 1292 1224 11.38      
32 Bu 1155 1095 20.08      
33 Bu 1030 977 15.44      
34 Bu 896 849 0.96      
35 Bu 877 832 5.33      
36 Bu 437 415 3.36      

Unscaled Zero Point Vibrational Energy (zpe) 23810.8 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 22572.6 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=FULL/3-21G*
ABC
0.16870 0.07063 0.04979

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

Point Group is C2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 1.360 1.110 0.000
C2 2.192 -0.173 0.000
C3 1.360 -1.260 0.000
C4 -1.360 -1.110 0.000
C5 -2.192 0.173 0.000
C6 -1.360 1.260 0.000
C7 0.046 0.745 0.000
C8 -0.046 -0.745 0.000
H9 1.787 2.108 0.000
H10 3.275 -0.186 0.000
H11 1.655 -2.302 0.000
H12 -1.787 -2.108 0.000
H13 -3.275 0.186 0.000
H14 -1.655 2.302 0.000

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 C7 C8 H9 H10 H11 H12 H13 H14
C11.52882.37033.51183.67382.72471.36412.32821.08482.31233.42474.50144.72693.2425
C21.52881.36893.67384.39723.83012.33392.30992.31571.08352.19564.42475.47884.5741
C32.37031.36892.72473.83013.70832.39751.49753.39442.19581.08263.25974.85574.6668
C43.51183.67382.72471.52882.37032.32821.36414.50144.72693.24251.08482.31233.4247
C53.67384.39723.83011.52881.36892.30992.33394.42475.47884.57412.31571.08352.1956
C62.72473.83013.70832.37031.36891.49752.39753.25974.85574.66683.39442.19581.0826
C71.36412.33392.39752.32822.30991.49751.49322.21103.36083.44573.39103.36802.3059
C82.32822.30991.49751.36412.33392.39751.49323.39103.36802.30592.21103.36083.4457
H91.08482.31573.39444.50144.42473.25972.21103.39102.73364.41115.52685.41523.4482
H102.31231.08352.19584.72695.47884.85573.36083.36802.73362.66485.41526.56115.5225
H113.42472.19561.08263.24254.57414.66683.44572.30594.41112.66483.44825.52255.6701
H124.50144.42473.25971.08482.31573.39443.39102.21105.52685.41523.44822.73364.4111
H134.72695.47884.85572.31231.08352.19583.36803.36085.41526.56115.52252.73362.6648
H143.24254.57414.66683.42472.19561.08262.30593.44573.44825.52255.67014.41112.6648

picture of Pentalene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 109.643 C1 C2 H10 123.644
C1 C7 C6 144.368 C1 C7 C8 109.055
C2 C1 C7 107.424 C2 C1 H9 123.864
C2 C3 C8 107.301 C2 C3 H11 126.773
C3 C2 H10 126.714 C3 C8 C4 144.368
C3 C8 C7 106.577 C4 C5 C6 109.643
C4 C5 H13 123.644 C4 C8 C7 109.055
C5 C4 C8 107.424 C5 C4 H12 123.864
C5 C6 C7 107.301 C5 C6 H14 126.773
C6 C5 H13 126.714 C6 C7 C8 106.577
C7 C1 H9 128.712 C7 C6 H14 125.926
C8 C3 H11 125.926 C8 C4 H12 128.712
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability