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All results from a given calculation for CHBr2 (dibromomethyl radical)

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 CS 2A'
Energy calculated at QCISD/3-21G*
 hartrees
Energy at 0K-5159.079455
Energy at 298.15K 
HF Energy-5158.719235
Nuclear repulsion energy334.103467
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
A' 3203 3078 1.21      
A' 627 602 10.20      
A' 445 428 24.00      
A' 180 173 0.13      
A" 1231 1183 56.80      
A" 781 751 87.19      

Unscaled Zero Point Vibrational Energy (zpe) 3233.7 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 3107.9 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/3-21G*
ABC
1.20025 0.04033 0.03905

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.006 0.862 0.000
H2 -0.486 1.830 0.000
Br3 0.006 -0.100 1.627
Br4 0.006 -0.100 -1.627

Atom - Atom Distances (Å)
  C1 H2 Br3 Br4
C11.08591.89041.8904
H21.08592.57212.5721
Br31.89042.57213.2541
Br41.89042.57213.2541

picture of dibromomethyl radical state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H2 C1 Br3 116.991 H2 C1 Br4 116.991
Br3 C1 Br4 118.796
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability