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All results from a given calculation for CH2I2 (Diiodomethane)

using model chemistry: MP2/CEP-31G

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-31G
 hartrees
Energy at 0K-29.168669
Energy at 298.15K 
HF Energy-29.034154
Nuclear repulsion energy29.998474
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-31G
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 3128 3022 14.34 126.00 0.09 0.17
2 A1 1410 1362 0.89 34.68 0.61 0.75
3 A1 467 451 0.16 21.17 0.22 0.36
4 A1 120 116 0.01 9.82 0.58 0.73
5 A2 1088 1052 0.00 28.77 0.75 0.86
6 B1 3230 3121 2.07 76.61 0.75 0.86
7 B1 763 738 21.03 11.85 0.75 0.86
8 B2 1227 1185 105.22 1.04 0.75 0.86
9 B2 574 555 45.59 13.56 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6003.5 cm-1
Scaled (by 0.9663) Zero Point Vibrational Energy (zpe) 5801.2 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-31G
ABC
0.73175 0.01907 0.01866

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-31G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.066
I2 0.000 1.864 -0.092
I3 0.000 -1.864 -0.092
H4 -0.910 0.000 1.690
H5 0.910 0.000 1.690

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.19502.19501.10341.1034
I22.19503.72882.73532.7353
I32.19503.72882.73532.7353
H41.10342.73532.73531.8199
H51.10342.73532.73531.8199

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 116.288 I2 C1 H4 107.369
I2 C1 H5 107.369 I3 C1 H4 107.369
I3 C1 H5 107.369 H4 C1 H5 111.109
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability