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All results from a given calculation for CH2I2 (Diiodomethane)

using model chemistry: QCISD/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at QCISD/3-21G*
 hartrees
Energy at 0K-13814.974066
Energy at 298.15K 
HF Energy-13814.621760
Nuclear repulsion energy603.287179
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 QCISD/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 A1 3124 3002 0.37      
2 A1 1486 1428 0.15      
3 A1 490 471 0.67      
4 A1 116 112 0.01      
5 A2 1100 1057 0.00      
6 B1 3206 3081 2.29      
7 B1 746 717 8.54      
8 B2 1192 1146 94.02      
9 B2 600 577 31.64      

Unscaled Zero Point Vibrational Energy (zpe) 6030.4 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 5795.9 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 QCISD/3-21G*
ABC
0.69966 0.01949 0.01903

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.099
I2 0.000 1.845 -0.094
I3 0.000 -1.845 -0.094
H4 -0.905 0.000 1.708
H5 0.905 0.000 1.708

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.19712.19711.09041.0904
I22.19713.68902.73302.7330
I32.19713.68902.73302.7330
H41.09042.73302.73301.8094
H51.09042.73302.73301.8094

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 114.180 I2 C1 H4 107.656
I2 C1 H5 107.656 I3 C1 H4 107.656
I3 C1 H5 107.656 H4 C1 H5 112.132
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability