return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C5H5 (cyclopentadienyl radical)

using model chemistry: CCSD(T)/TZVP

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 2 yes C2V 2B1

Conformer 1 (D5H)

Jump to S1C2
Vibrational Frequencies calculated at CCSD(T)/TZVP
Rotational Constants (cm-1) from geometry optimized at CCSD(T)/TZVP
See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)/TZVP
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (C2V)

Jump to S1C1
Energy calculated at CCSD(T)/TZVP
 hartrees
Energy at 0K-192.980030
Energy at 298.15K 
HF Energy-192.250549
Nuclear repulsion energy148.364321
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 CCSD(T)/TZVP
Rotational Constants (cm-1) from geometry optimized at CCSD(T)/TZVP
See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)/TZVP

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.226
C2 0.000 1.128 0.396
C3 0.000 0.681 -1.009
C4 0.000 -0.681 -1.009
C5 0.000 -1.128 0.396
H6 0.000 0.000 2.306
H7 0.000 2.161 0.719
H8 0.000 1.337 -1.869
H9 0.000 -1.337 -1.869
H10 0.000 -2.161 0.719

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 H6 H7 H8 H9 H10
C11.40062.33682.33681.40061.08042.22023.37153.37152.2202
C21.40061.47442.29062.25592.21871.08282.27453.34723.3052
C32.33681.47441.36232.29063.38502.27531.08122.19343.3266
C42.33682.29061.36231.47443.38503.32662.19341.08122.2753
C51.40062.25592.29061.47442.21873.30523.34722.27451.0828
H61.08042.21873.38503.38502.21872.68204.38434.38432.6820
H72.22021.08282.27533.32663.30522.68202.71614.35134.3230
H83.37152.27451.08122.19343.34724.38432.71612.67334.3513
H93.37153.34722.19341.08122.27454.38434.35132.67332.7161
H102.22023.30523.32662.27531.08282.68204.32304.35132.7161

picture of cyclopentadienyl radical state 1 conformation 2
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 108.717 C1 C2 H7 126.296
C1 C5 C4 108.717 C1 C5 H10 126.296
C2 C1 C5 107.287 C2 C1 H6 126.356
C2 C3 C4 107.639 C2 C3 H8 125.040
C3 C2 H7 124.987 C3 C4 C5 107.639
C3 C4 H9 127.320 C4 C3 H8 127.320
C4 C5 H10 124.987 C5 C1 H6 126.356
C5 C4 H9 125.040
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability