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All results from a given calculation for CH2I2 (Diiodomethane)

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 C2V 1A1
Energy calculated at MP2/CEP-121G
 hartrees
Energy at 0K-29.180423
Energy at 298.15K 
HF Energy-29.038317
Nuclear repulsion energy30.094090
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 A1 3072 2998 10.83 106.33 0.10 0.17
2 A1 1417 1383 0.96 29.89 0.59 0.74
3 A1 471 459 0.01 20.52 0.22 0.36
4 A1 121 118 0.01 9.87 0.56 0.72
5 A2 1105 1078 0.00 28.49 0.75 0.86
6 B1 3175 3099 1.72 63.71 0.75 0.86
7 B1 757 739 21.17 8.28 0.75 0.86
8 B2 1227 1198 106.12 1.06 0.75 0.86
9 B2 578 564 44.47 14.49 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 5961.3 cm-1
Scaled (by 0.976) Zero Point Vibrational Energy (zpe) 5818.2 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
0.73619 0.01915 0.01874

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.064
I2 0.000 1.860 -0.092
I3 0.000 -1.860 -0.092
H4 -0.904 0.000 1.683
H5 0.904 0.000 1.683

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.19042.19041.09491.0949
I22.19043.72082.72522.7252
I32.19043.72082.72522.7252
H41.09492.72522.72521.8071
H51.09492.72522.72521.8071

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 116.278 I2 C1 H4 107.345
I2 C1 H5 107.345 I3 C1 H4 107.345
I3 C1 H5 107.345 H4 C1 H5 111.227
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability