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

using model chemistry: MP2/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/3-21G
 hartrees
Energy at 0K-151.435727
Energy at 298.15K-151.439086
HF Energy-151.187320
Counterpoise corrected energy-75.585198
CP Energy at 298.15K-75.588072
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy36.921818
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 MP2/3-21G
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' 3632 3467 49.25      
2 A' 3520 3360 2.03      
3 A' 3441 3284 248.18      
4 A' 1788 1707 59.37      
5 A' 1720 1642 68.46      
6 A' 532 508 58.12      
7 A' 281 268 221.11      
8 A' 218 208 243.19      
9 A" 3667 3500 13.68      
10 A" 850 811 192.84      
11 A" 224 214 58.46      
12 A" 138 132 180.95      

Unscaled Zero Point Vibrational Energy (zpe) 10005.6 cm-1
Scaled (by 0.9545) Zero Point Vibrational Energy (zpe) 9550.3 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 MP2/3-21G
ABC
6.48215 0.23237 0.23211

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/3-21G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.168 0.505 0.000
O2 0.004 1.482 0.000
O3 0.004 -1.395 0.000
H4 0.888 1.921 0.000
H5 -0.559 -1.559 0.798
H6 -0.559 -1.559 -0.798

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99051.90751.58832.32922.3292
O20.99052.87730.98683.19363.1936
O31.90752.87733.43210.99070.9907
H41.58830.98683.43213.85213.8521
H52.32923.19360.99073.85211.5969
H62.32923.19360.99073.85211.5969

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 106.892 H1 O3 H5 102.294
H1 O3 H6 102.294 O2 H1 O3 165.536
H5 O3 H6 107.400
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability