return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for CH3I (methyl iodide)

using model chemistry: HF/CEP-31G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C3V 1A1
Energy calculated at HF/CEP-31G
 hartrees
Energy at 0K-18.422465
Energy at 298.15K 
HF Energy-18.422465
Nuclear repulsion energy17.661295
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 HF/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 3270 2947 56.91 203.63 0.00 0.00
2 A1 1441 1299 69.20 13.03 0.24 0.39
3 A1 529 476 17.89 75.63 0.37 0.54
4 E 3413 3077 17.19 94.13 0.75 0.86
4 E 3413 3077 17.19 94.13 0.75 0.86
5 E 1598 1440 8.14 22.09 0.75 0.86
5 E 1598 1440 8.14 22.09 0.75 0.86
6 E 1002 903 12.83 15.73 0.75 0.86
6 E 1002 903 12.83 15.73 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 8632.7 cm-1
Scaled (by 0.9014) Zero Point Vibrational Energy (zpe) 7781.5 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 HF/CEP-31G
ABC
5.23004 0.24232 0.24232

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

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.848
I2 0.000 0.000 0.332
H3 0.000 1.033 -2.170
H4 0.894 -0.516 -2.170
H5 -0.894 -0.516 -2.170

Atom - Atom Distances (Å)
  C1 I2 H3 H4 H5
C12.18031.08141.08141.0814
I22.18032.70662.70662.7066
H31.08142.70661.78841.7884
H41.08142.70661.78841.7884
H51.08142.70661.78841.7884

picture of methyl iodide state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
I2 C1 H3 107.300 I2 C1 H4 107.300
I2 C1 H5 107.300 H3 C1 H4 111.552
H3 C1 H5 111.552 H4 C1 H5 111.552
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.621      
2 I 0.051      
3 H 0.190      
4 H 0.190      
5 H 0.190      


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 -2.220 2.220
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -28.459 0.000 0.000
y 0.000 -28.459 0.000
z 0.000 0.000 -22.929
Traceless
 xyz
x -2.765 0.000 0.000
y 0.000 -2.765 0.000
z 0.000 0.000 5.530
Polar
3z2-r211.061
x2-y20.000
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 1.876 0.000 0.000
y 0.000 1.876 0.000
z 0.000 0.000 7.598


<r2> (average value of r2) Å2
<r2> 48.383
(<r2>)1/2 6.956