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All results from a given calculation for CH2I2 (Diiodomethane)

using model chemistry: PBEPBE/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 PBEPBE/3-21G
 hartrees
Energy at 0K-13818.944701
Energy at 298.15K 
HF Energy-13818.944701
Nuclear repulsion energy596.503766
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 PBEPBE/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 3083 3055 0.77 96.32 0.08 0.15
2 A1 1426 1413 0.40 31.12 0.65 0.79
3 A1 464 460 0.63 15.24 0.17 0.29
4 A1 115 114 0.01 11.26 0.48 0.65
5 A2 1071 1061 0.00 15.85 0.75 0.86
6 B1 3174 3145 0.58 59.47 0.75 0.86
7 B1 722 716 14.82 5.30 0.75 0.86
8 B2 1153 1143 98.36 0.51 0.75 0.86
9 B2 553 548 99.47 8.11 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 5880.5 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 5827.0 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 PBEPBE/3-21G
ABC
0.73688 0.01887 0.01847

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.064
I2 0.000 1.874 -0.092
I3 0.000 -1.874 -0.092
H4 -0.907 0.000 1.679
H5 0.907 0.000 1.679

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.20212.20211.09541.0954
I22.20213.74862.73312.7331
I32.20213.74862.73312.7331
H41.09542.73312.73311.8137
H51.09542.73312.73311.8137

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 116.669 I2 C1 H4 107.125
I2 C1 H5 107.125 I3 C1 H4 107.125
I3 C1 H5 107.125 H4 C1 H5 111.761
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.955      
2 I 0.175      
3 I 0.175      
4 H 0.303      
5 H 0.303      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 1.376 1.376
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -63.941 0.000 0.000
y 0.000 -63.597 0.000
z 0.000 0.000 -61.109
Traceless
 xyz
x -1.588 0.000 0.000
y 0.000 -1.072 0.000
z 0.000 0.000 2.660
Polar
3z2-r25.320
x2-y2-0.344
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.539 0.000 0.000
y 0.000 12.894 0.000
z 0.000 0.000 4.989


<r2> (average value of r2) Å2
<r2> 426.624
(<r2>)1/2 20.655