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

using model chemistry: MP2=FULL/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=FULL/3-21G
 hartrees
Energy at 0K-151.439391
Energy at 298.15K-151.442747
HF Energy-151.187346
Counterpoise corrected energy-151.439391
CP Energy at 298.15K-151.442747
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy36.924188
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=FULL/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' 3633 3469 49.53      
2 A' 3521 3362 2.05      
3 A' 3442 3287 248.55      
4 A' 1788 1707 59.55      
5 A' 1720 1642 68.57      
6 A' 531 507 58.66      
7 A' 280 268 215.64      
8 A' 218 208 247.62      
9 A" 3668 3503 13.82      
10 A" 850 812 193.34      
11 A" 225 215 56.84      
12 A" 138 132 182.34      

Unscaled Zero Point Vibrational Energy (zpe) 10006.7 cm-1
Scaled (by 0.9548) Zero Point Vibrational Energy (zpe) 9554.4 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=FULL/3-21G
ABC
6.48584 0.23238 0.23213

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/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 1.803 0.000
H5 -0.560 -1.535 0.791
H6 -0.560 -1.535 -0.791

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99491.81391.57922.24512.2451
O20.99492.80230.98733.14093.1409
O31.81392.80233.28630.98980.9898
H41.57920.98733.28633.73983.7398
H52.24513.14090.98983.73981.5817
H62.24513.14090.98983.73981.5817

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 105.637 H1 O3 H5 102.386
H1 O3 H6 102.386 O2 H1 O3 171.886
H5 O3 H6 106.060
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability