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All results from a given calculation for CH2I2 (Diiodomethane)

using model chemistry: mPW1PW91/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at mPW1PW91/3-21G*
 hartrees
Energy at 0K-13821.210425
Energy at 298.15K 
HF Energy-13821.210425
Nuclear repulsion energy610.754439
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 mPW1PW91/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 A1 3162 3003 0.00 75.77 0.08 0.14
2 A1 1471 1397 0.33 26.00 0.62 0.76
3 A1 508 482 0.37 17.65 0.09 0.17
4 A1 117 111 0.01 5.54 0.39 0.56
5 A2 1105 1050 0.00 5.76 0.75 0.86
6 B1 3251 3087 5.43 50.36 0.75 0.86
7 B1 741 704 11.56 1.66 0.75 0.86
8 B2 1188 1128 81.14 0.01 0.75 0.86
9 B2 614 583 49.05 7.87 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6078.0 cm-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 5771.7 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 mPW1PW91/3-21G*
ABC
0.72989 0.01993 0.01947

See section I.F.4 to change rotational constant units
Geometric Data calculated at mPW1PW91/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.072
I2 0.000 1.824 -0.092
I3 0.000 -1.824 -0.092
H4 -0.899 0.000 1.683
H5 0.899 0.000 1.683

Atom - Atom Distances (Å)
  C1 I2 I3 H4 H5
C12.16372.16371.08711.0871
I22.16373.64762.69932.6993
I32.16373.64762.69932.6993
H41.08712.69932.69931.7982
H51.08712.69932.69931.7982

picture of Diiodomethane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 I3 114.897 I2 C1 H4 107.603
I2 C1 H5 107.603 I3 C1 H4 107.603
I3 C1 H5 107.603 H4 C1 H5 111.602
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.759      
2 I 0.081      
3 I 0.081      
4 H 0.299      
5 H 0.299      


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 1.208 1.208
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -63.769 0.000 0.000
y 0.000 -62.580 0.000
z 0.000 0.000 -60.424
Traceless
 xyz
x -2.267 0.000 0.000
y 0.000 -0.483 0.000
z 0.000 0.000 2.751
Polar
3z2-r25.501
x2-y2-1.189
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 6.685 0.000 0.000
y 0.000 13.807 0.000
z 0.000 0.000 7.510


<r2> (average value of r2) Å2
<r2> 406.554
(<r2>)1/2 20.163