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All results from a given calculation for CH2I2 (Diiodomethane)

using model chemistry: CISD/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 CISD/3-21G
 hartrees
Energy at 0K-13814.653718
Energy at 298.15K 
HF Energy-13814.487574
Nuclear repulsion energy598.140973
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 CISD/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 3183 2996 2.75      
2 A1 1515 1426 0.08      
3 A1 478 450 0.59      
4 A1 121 114 0.00      
5 A2 1133 1066 0.00      
6 B1 3260 3069 0.14      
7 B1 759 714 11.84      
8 B2 1227 1155 111.62      
9 B2 608 572 37.50      

Unscaled Zero Point Vibrational Energy (zpe) 6141.0 cm-1
Scaled (by 0.9413) Zero Point Vibrational Energy (zpe) 5780.5 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 CISD/3-21G
ABC
0.73346 0.01900 0.01858

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.068
I2 0.000 1.868 -0.092
I3 0.000 -1.868 -0.092
H4 -0.894 0.000 1.684
H5 0.894 0.000 1.684

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.19922.19921.08591.0859
I22.19923.73632.72862.7286
I32.19923.73632.72862.7286
H41.08592.72862.72861.7883
H51.08592.72862.72861.7883

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 116.311 I2 C1 H4 107.419
I2 C1 H5 107.419 I3 C1 H4 107.419
I3 C1 H5 107.419 H4 C1 H5 110.863
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability