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All results from a given calculation for H2OH2O (water dimer)

using model chemistry: MP2_cp_opt/3-21G

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_cp_opt/3-21G
 hartrees
Energy at 0K-75.585198
Energy at 298.15K-75.588072
HF Energy-75.585198
Nuclear repulsion energy8.911136
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_cp_opt/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 A' 3631 3466 48.37      
2 A' 3537 3377 3.22      
3 A' 3465 3307 139.24      
4 A' 1769 1688 88.17      
5 A' 1733 1654 51.29      
6 A' 379 362 190.93      
7 A' 192 184 25.17      
8 A' 177 169 268.30      
9 A" 3693 3525 4.93      
10 A" 690 659 288.70      
11 A" 183 174 68.30      
12 A" 108 104 90.30      

Unscaled Zero Point Vibrational Energy (zpe) 9778.9 cm-1
Scaled (by 0.9545) Zero Point Vibrational Energy (zpe) 9333.9 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 MP2_cp_opt/3-21G
ABC
7.58105 0.21045 0.20971

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2_cp_opt/3-21G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 -0.051 0.556 0.000
O2 -0.021 1.550 0.000
O3 -0.021 -1.367 0.000
H4 0.941 1.778 0.000
H5 -0.279 -1.902 0.789
H6 -0.279 -1.902 -0.789

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99441.92311.57382.59132.5913
O20.99442.91690.98803.55013.5501
O31.92312.91693.28860.98730.9873
H41.57380.98803.28863.95613.9561
H52.59133.55010.98733.95611.5773
H62.59133.55010.98733.95611.5773

picture of water dimer state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H1 O2 H4 105.099 H1 O3 H5 122.519
H1 O3 H6 122.519 O2 H1 O3 177.346
H5 O3 H6 106.032
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability