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

using model chemistry: QCISD/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 QCISD/3-21G*
 hartrees
Energy at 0K-6927.536548
Energy at 298.15K 
HF Energy-6927.303022
Nuclear repulsion energy116.561909
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 QCISD/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 3079 2959 10.52      
2 A1 1356 1304 30.34      
3 A1 535 514 4.19      
4 E 3180 3057 1.32      
4 E 3180 3057 1.32      
5 E 1545 1485 6.59      
5 E 1545 1485 6.59      
6 E 930 893 7.75      
6 E 930 893 7.75      

Unscaled Zero Point Vibrational Energy (zpe) 8139.7 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 7823.0 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 QCISD/3-21G*
ABC
5.13223 0.23649 0.23649

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

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.871
I2 0.000 0.000 0.336
H3 0.000 1.042 -2.198
H4 0.903 -0.521 -2.198
H5 -0.903 -0.521 -2.198

Atom - Atom Distances (Å)
  C1 I2 H3 H4 H5
C12.20681.09241.09241.0924
I22.20682.73982.73982.7398
H31.09242.73981.80531.8053
H41.09242.73981.80531.8053
H51.09242.73981.80531.8053

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 107.416 I2 C1 H4 107.416
I2 C1 H5 107.416 H3 C1 H4 111.446
H3 C1 H5 111.446 H4 C1 H5 111.446
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability