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

using model chemistry: MP2_cp/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/3-21G
 hartrees
Energy at 0K-151.423070
Energy at 298.15K-151.416756
Nuclear repulsion energy 
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
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability