return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

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

using model chemistry: PBEPBE/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 PBEPBE/3-21G*
 hartrees
Energy at 0K-2601.260084
Energy at 298.15K 
HF Energy-2601.260084
Nuclear repulsion energy88.155355
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 PBEPBE/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 3023 2882 14.01      
2 A1 1338 1275 10.64      
3 A1 609 581 8.72      
4 E 3127 2981 3.94      
4 E 3127 2981 3.94      
5 E 1493 1424 9.42      
5 E 1493 1424 9.42      
6 E 952 908 9.98      
6 E 952 908 9.98      

Unscaled Zero Point Vibrational Energy (zpe) 8056.4 cm-1
Scaled (by 0.9535) Zero Point Vibrational Energy (zpe) 7681.8 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 PBEPBE/3-21G*
ABC
5.11376 0.31228 0.31228

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

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 -1.538
Br2 0.000 0.000 0.425
H3 0.000 1.044 -1.878
H4 0.904 -0.522 -1.878
H5 -0.904 -0.522 -1.878

Atom - Atom Distances (Å)
  C1 Br2 H3 H4 H5
C11.96251.09811.09811.0981
Br21.96252.52822.52822.5282
H31.09812.52821.80861.8086
H41.09812.52821.80861.8086
H51.09812.52821.80861.8086

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 108.035 Br2 C1 H4 108.035
Br2 C1 H5 108.035 H3 C1 H4 110.868
H3 C1 H5 110.868 H4 C1 H5 110.868
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.674      
2 Br -0.070      
3 H 0.248      
4 H 0.248      
5 H 0.248      


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 -1.721 1.721
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -25.339 0.000 0.000
y 0.000 -25.339 0.000
z 0.000 0.000 -21.471
Traceless
 xyz
x -1.934 0.000 0.000
y 0.000 -1.934 0.000
z 0.000 0.000 3.867
Polar
3z2-r27.735
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 2.910 0.000 0.000
y 0.000 2.909 0.000
z 0.000 0.000 5.025


<r2> (average value of r2) Å2
<r2> 49.371
(<r2>)1/2 7.026