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

using model chemistry: QCISD(T)/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(T)/3-21G*
 hartrees
Energy at 0K-6927.541664
Energy at 298.15K 
HF Energy-6927.302850
Nuclear repulsion energy116.298277
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(T)/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 3064 2922        
2 A1 1345 1283        
3 A1 526 501        
4 E 3168 3021        
4 E 3167 3021        
5 E 1539 1468        
5 E 1539 1467        
6 E 921 879        
6 E 921 879        

Unscaled Zero Point Vibrational Energy (zpe) 8094.7 cm-1
Scaled (by 0.9537) Zero Point Vibrational Energy (zpe) 7719.9 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(T)/3-21G*
ABC
5.11567 0.23537 0.23537

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

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.876
I2 0.000 0.000 0.337
H3 0.000 1.044 -2.201
H4 0.904 -0.522 -2.201
H5 -0.904 -0.522 -2.201

Atom - Atom Distances (Å)
  C1 I2 H3 H4 H5
C12.21271.09351.09341.0934
I22.21272.74422.74422.7442
H31.09352.74421.80821.8082
H41.09342.74421.80821.8082
H51.09342.74421.80821.8082

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 111.553
H3 C1 H5 111.553 H4 C1 H5 111.553
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability