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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-151.439077
HF Energy-151.187329
Counterpoise corrected energy 
CP Energy at 298.15K 
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy36.919636
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 3456 49.41      
2 A' 3520 3349 2.07      
3 A' 3442 3274 247.92      
4 A' 1788 1701 59.47      
5 A' 1720 1636 68.50      
6 A' 531 505 58.59      
7 A' 280 267 216.65      
8 A' 217 207 246.55      
9 A" 3667 3489 13.72      
10 A" 849 808 193.06      
11 A" 225 214 57.32      
12 A" 138 131 181.84      

Unscaled Zero Point Vibrational Energy (zpe) 10004.9 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 9517.7 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
6.48326 0.23231 0.23206

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 0.097 0.461 0.000
O2 0.006 1.452 0.000
O3 0.006 -1.351 0.000
H4 0.928 1.804 0.000
H5 -0.561 -1.535 0.791
H6 -0.561 -1.535 -0.791

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99491.81451.57922.24512.2451
O20.99492.80290.98733.14073.1407
O31.81452.80293.28690.98990.9899
H41.57920.98733.28693.73983.7398
H52.24513.14070.98993.73981.5816
H62.24513.14070.98993.73981.5816

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 105.621 H1 O3 H5 102.345
H1 O3 H6 102.345 O2 H1 O3 171.856
H5 O3 H6 106.041
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability