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

using model chemistry: MP2/6-31+G**

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/6-31+G**
 hartrees
Energy at 0K-205.193674
Energy at 298.15K 
HF Energy-204.642374
Nuclear repulsion energy68.915056
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 MP2/6-31+G**
Rotational Constants (cm-1) from geometry optimized at MP2/6-31+G**
ABC
3.02561 0.41331 0.36363

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31+G**

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.774 -0.135 0.000
O2 0.909 -0.582 0.000
N3 0.000 0.525 0.000
O4 -1.130 0.140 0.000

Atom - Atom Distances (Å)
  H1 O2 N3 O4
H10.97401.89312.9175
O20.97401.43222.1629
N31.89311.43221.1943
O42.91752.16291.1943

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 102.075 O2 N3 O4 110.546
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability