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: mPW1PW91/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C3V 1A1
Energy calculated at mPW1PW91/3-21G
 hartrees
Energy at 0K-6930.681195
Energy at 298.15K 
HF Energy-6930.681195
Nuclear repulsion energy117.485587
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
4/u)
Dep P Dep U
1 A1 3128 2986 10.14      
2 A1 1359 1297 22.21      
3 A1 543 518 5.17      
4 E 3243 3096 0.95      
4 E 3243 3096 0.95      
5 E 1534 1464 14.73      
5 E 1534 1464 14.73      
6 E 937 895 12.39      
6 E 937 895 12.39      

Unscaled Zero Point Vibrational Energy (zpe) 8229.4 cm-1
Scaled (by 0.9546) Zero Point Vibrational Energy (zpe) 7855.8 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
5.19588 0.24043 0.24043

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

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.853
I2 0.000 0.000 0.334
H3 0.000 1.036 -2.185
H4 0.897 -0.518 -2.185
H5 -0.897 -0.518 -2.185

Atom - Atom Distances (Å)
  C1 I2 H3 H4 H5
C12.18701.08771.08771.0877
I22.18702.72322.72322.7232
H31.08772.72321.79421.7942
H41.08772.72321.79421.7942
H51.08772.72321.79421.7942

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 107.748 I2 C1 H4 107.748
I2 C1 H5 107.748 H3 C1 H4 111.139
H3 C1 H5 111.139 H4 C1 H5 111.139
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 -0.925      
2 I 0.110      
3 H 0.272      
4 H 0.272      
5 H 0.272      


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 -1.813 1.813
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -36.116 0.000 0.000
y 0.000 -36.116 0.000
z 0.000 0.000 -31.116
Traceless
 xyz
x -2.500 0.000 0.000
y 0.000 -2.500 0.000
z 0.000 0.000 5.000
Polar
3z2-r29.999
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 2.568 0.000 0.000
y 0.000 2.568 0.000
z 0.000 0.000 6.477


<r2> (average value of r2) Å2
<r2> 65.565
(<r2>)1/2 8.097