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

using model chemistry: PBE1PBE/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 PBE1PBE/3-21G*
 hartrees
Energy at 0K-2601.357597
Energy at 298.15K 
HF Energy-2601.357597
Nuclear repulsion energy88.984953
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 PBE1PBE/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 3106 2981 13.36 100.50 0.00 0.00
2 A1 1393 1337 9.38 2.31 0.57 0.73
3 A1 647 621 9.31 15.82 0.28 0.44
4 E 3213 3084 2.40 56.78 0.75 0.86
4 E 3213 3084 2.40 56.78 0.75 0.86
5 E 1538 1477 10.62 18.40 0.75 0.86
5 E 1538 1477 10.62 18.40 0.75 0.86
6 E 992 952 10.26 7.08 0.75 0.86
6 E 992 952 10.26 7.08 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 8315.9 cm-1
Scaled (by 0.9598) Zero Point Vibrational Energy (zpe) 7981.6 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 PBE1PBE/3-21G*
ABC
5.19719 0.31834 0.31834

See section I.F.4 to change rotational constant units
Geometric Data calculated at PBE1PBE/3-21G*

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.522
Br2 0.000 0.000 0.421
H3 0.000 1.036 -1.862
H4 0.897 -0.518 -1.862
H5 -0.897 -0.518 -1.862

Atom - Atom Distances (Å)
  C1 Br2 H3 H4 H5
C11.94281.09021.09021.0902
Br21.94282.50702.50702.5070
H31.09022.50701.79401.7940
H41.09022.50701.79401.7940
H51.09022.50701.79401.7940

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 108.184 Br2 C1 H4 108.184
Br2 C1 H5 108.184 H3 C1 H4 110.727
H3 C1 H5 110.727 H4 C1 H5 110.727
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBE1PBE/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.703      
2 Br -0.077      
3 H 0.260      
4 H 0.260      
5 H 0.260      


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 -1.788 1.788
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -25.354 0.000 0.000
y 0.000 -25.354 0.000
z 0.000 0.000 -21.458
Traceless
 xyz
x -1.948 0.000 0.000
y 0.000 -1.948 0.000
z 0.000 0.000 3.896
Polar
3z2-r27.791
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 2.872 0.000 0.000
y 0.000 2.872 0.000
z 0.000 0.000 4.946


<r2> (average value of r2) Å2
<r2> 48.743
(<r2>)1/2 6.982