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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-6930.751292
Energy at 298.15K 
HF Energy-6930.751292
Nuclear repulsion energy118.258103
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 3120 2963 7.91      
2 A1 1349 1281 15.47      
3 A1 562 534 3.36      
4 E 3233 3070 0.18      
4 E 3233 3070 0.18      
5 E 1531 1454 10.72      
5 E 1531 1454 10.72      
6 E 927 881 11.41      
6 E 927 881 11.41      

Unscaled Zero Point Vibrational Energy (zpe) 8207.5 cm-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 7793.8 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
5.18949 0.24398 0.24398

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 -1.839
I2 0.000 0.000 0.331
H3 0.000 1.037 -2.171
H4 0.898 -0.518 -2.171
H5 -0.898 -0.518 -2.171

Atom - Atom Distances (Å)
  C1 I2 H3 H4 H5
C12.17001.08831.08831.0883
I22.17002.70792.70792.7079
H31.08832.70791.79531.7953
H41.08832.70791.79531.7953
H51.08832.70791.79531.7953

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 107.743 I2 C1 H4 107.743
I2 C1 H5 107.743 H3 C1 H4 111.143
H3 C1 H5 111.143 H4 C1 H5 111.143
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 -0.797      
2 I 0.011      
3 H 0.262      
4 H 0.262      
5 H 0.262      


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 -1.735 1.735
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -36.068 0.000 0.000
y 0.000 -36.068 0.000
z 0.000 0.000 -30.371
Traceless
 xyz
x -2.849 0.000 0.000
y 0.000 -2.849 0.000
z 0.000 0.000 5.698
Polar
3z2-r211.396
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 4.320 0.000 0.000
y 0.000 4.320 0.000
z 0.000 0.000 6.950


<r2> (average value of r2) Å2
<r2> 64.797
(<r2>)1/2 8.050