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

using model chemistry: MP2/CEP-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/CEP-31G
 hartrees
Energy at 0K-33.893372
Energy at 298.15K 
HF Energy-33.663929
Counterpoise corrected energy 
CP Energy at 298.15K 
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy25.474344
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/CEP-31G
Rotational Constants (cm-1) from geometry optimized at MP2/CEP-31G
See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-31G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 -0.017 0.512 0.000
O2 -0.027 1.503 0.000
O3 -0.027 -1.333 0.000
H4 0.890 1.852 0.000
H5 -0.220 -1.861 0.806
H6 -0.220 -1.861 -0.806

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99111.84501.61882.51392.5139
O20.99112.83600.98163.46423.4642
O31.84502.83603.31480.98240.9824
H41.61880.98163.31483.95813.9581
H52.51393.46420.98243.95811.6122
H62.51393.46420.98243.95811.6122

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 110.278 H1 O3 H5 122.550
H1 O3 H6 122.550 O2 H1 O3 179.132
H5 O3 H6 110.276
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability