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All results from a given calculation for HNO2 (Nitrous acid)

using model chemistry: CCD/6-31G**

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at CCD/6-31G**
 hartrees
Energy at 0K-205.173821
Energy at 298.15K-205.176166
HF Energy-204.638866
Nuclear repulsion energy69.873931
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 CCD/6-31G**
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3875 3633 67.30      
2 A' 1807 1694 85.89      
3 A' 1370 1285 194.21      
4 A' 929 871 180.73      
5 A' 685 642 48.60      
6 A" 572 536 118.06      

Unscaled Zero Point Vibrational Energy (zpe) 4618.7 cm-1
Scaled (by 0.9376) Zero Point Vibrational Energy (zpe) 4330.5 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 CCD/6-31G**
ABC
3.08362 0.42721 0.37522

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCD/6-31G**

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.759 -0.127 0.000
O2 0.896 -0.563 0.000
N3 0.000 0.519 0.000
O4 -1.116 0.124 0.000

Atom - Atom Distances (Å)
  H1 O2 N3 O4
H10.96691.87432.8865
O20.96691.40482.1263
N31.87431.40481.1840
O42.88652.12631.1840

picture of Nitrous acid state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H1 O2 N3 102.863 O2 N3 O4 110.152
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability