return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

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

using model chemistry: MP2/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/6-31G*
 hartrees
Energy at 0K-152.405355
Energy at 298.15K-152.408177
HF Energy-152.028265
Counterpoise corrected energy-76.009734
CP Energy at 298.15K-76.012541
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy36.544680
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 MP2/6-31G*
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' 3884 3662 88.95      
2 A' 3762 3547 15.75      
3 A' 3707 3496 216.76      
4 A' 1767 1666 89.15      
5 A' 1733 1634 87.56      
6 A' 437 412 40.27      
7 A' 214 202 171.24      
8 A' 144 136 262.02      
9 A" 3894 3672 67.57      
10 A" 676 637 162.80      
11 A" 159 150 186.08      
12 A" 90 85 47.82      

Unscaled Zero Point Vibrational Energy (zpe) 10233.5 cm-1
Scaled (by 0.943) Zero Point Vibrational Energy (zpe) 9650.2 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 MP2/6-31G*
ABC
6.69062 0.21632 0.21589

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.060 0.552 0.000
O2 0.008 1.524 0.000
O3 0.008 -1.413 0.000
H4 0.931 1.812 0.000
H5 -0.557 -1.624 0.763
H6 -0.557 -1.624 -0.763

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.97301.96601.53202.38682.3868
O20.97302.93680.96773.28733.2873
O31.96602.93683.35530.97240.9724
H41.53200.96773.35533.82153.8215
H52.38683.28730.97243.82151.5258
H62.38683.28730.97243.82151.5258

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 104.265 H1 O3 H5 103.406
H1 O3 H6 103.406 O2 H1 O3 175.363
H5 O3 H6 103.361
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability