National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
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III.D.1.a.

All results from a given calculation for H2NO (nitroxide)

using model chemistry: MP4/3-21G

States and conformations

State Conformation minimum conformation conformer description state description
1 1 no C2V 2B1
1 2 yes CS 2A'

Conformer 1 (C2V)

Jump to S1C2
Energy calculated at MP4/3-21G
 hartrees
Energy at 0K-129.889469
Energy at 298.15K 
HF Energy-129.665349
Nuclear repulsion energy33.606720
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 MP4/3-21G
Mode Number Symmetry Frequency (cm-1) Scaled Frequency (cm-1) IR Intensities (km mol-1)
1 A1 3440 3336  
2 A1 1703 1652  
3 A1 1237 1200  
4 B1 208i 202i  
5 B2 3593 3485  
6 B2 1210 1174  

Unscaled Zero Point Vibrational Energy (zpe) 5487.5 cm-1
Scaled (by 0.9698) Zero Point Vibrational Energy (zpe) 5321.8 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 MP4/3-21G
ABC
10.77347 1.02050 0.93220

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 -0.577
O2 0.000 0.000 0.776
H3 0.000 0.881 -1.083
H4 0.000 -0.881 -1.083

Atom - Atom Distances (Å)

  N1 O2 H3 H4
N11.35341.01561.0156
O21.35342.05672.0567
H31.01562.05671.7622
H41.01562.05671.7622

picture of nitroxide
More geometry information

Calculated Bond Angles

atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O2 N1 H3 119.821 O2 N1 H4 119.821
H3 N1 H4 120.357
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (CS)

Jump to S1C1
Energy calculated at MP4/3-21G
 hartrees
Energy at 0K-129.889521
Energy at 298.15K 
HF Energy-129.665646
Nuclear repulsion energy33.560142
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 MP4/3-21G
Mode Number Symmetry Frequency (cm-1) Scaled Frequency (cm-1) IR Intensities (km mol-1)
1 A' 3426 3322  
2 A' 1703 1651  
3 A' 1224 1187  
4 A' 287 279  
5 A" 3575 3467  
6 A" 1219 1182  

Unscaled Zero Point Vibrational Energy (zpe) 5717.0 cm-1
Scaled (by 0.9698) Zero Point Vibrational Energy (zpe) 5544.4 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 MP4/3-21G
ABC
10.61313 1.01753 0.93208

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/3-21G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -0.018 0.581 0.000
O2 -0.018 -0.776 0.000
H3 0.131 1.072 0.878
H4 0.131 1.072 -0.878

Atom - Atom Distances (Å)

  N1 O2 H3 H4
N11.35661.01681.0168
O21.35662.05092.0509
H31.01682.05091.7558
H41.01682.05091.7558

picture of nitroxide
More geometry information

Calculated Bond Angles

atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O2 N1 H3 118.871 O2 N1 H4 118.871
H3 N1 H4 119.396
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability