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All results from a given calculation for CH3Br (methyl bromide)

using model chemistry: MP2=FULL/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 MP2=FULL/3-21G*
 hartrees
Energy at 0K-2599.899350
Energy at 298.15K 
HF Energy-2599.663293
Nuclear repulsion energy88.250304
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 MP2=FULL/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 3131 2969 12.64      
2 A1 1425 1351 19.68      
3 A1 632 599 11.67      
4 E 3235 3066 3.08      
4 E 3235 3066 3.08      
5 E 1581 1499 6.74      
5 E 1581 1499 6.74      
6 E 1013 960 6.64      
6 E 1013 960 6.64      

Unscaled Zero Point Vibrational Energy (zpe) 8422.2 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 7984.3 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 MP2=FULL/3-21G*
ABC
5.18906 0.31233 0.31233

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.540
Br2 0.000 0.000 0.425
H3 0.000 1.037 -1.873
H4 0.898 -0.518 -1.873
H5 -0.898 -0.518 -1.873

Atom - Atom Distances (Å)
  C1 Br2 H3 H4 H5
C11.96451.08861.08861.0886
Br21.96452.52012.52012.5201
H31.08862.52011.79541.7954
H41.08862.52011.79541.7954
H51.08862.52011.79541.7954

picture of methyl bromide state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
Br2 C1 H3 107.785 Br2 C1 H4 107.785
Br2 C1 H5 107.785 H3 C1 H4 111.103
H3 C1 H5 111.103 H4 C1 H5 111.103
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability