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

using model chemistry: CCSD(T)/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 CCSD(T)/3-21G
 hartrees
Energy at 0K-151.453320
Energy at 298.15K-151.456652
HF Energy-151.186617
Counterpoise corrected energy-75.584026
CP Energy at 298.15K 
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy36.715286
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 CCSD(T)/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' 3547 3514        
2 A' 3444 3411        
3 A' 3402 3370        
4 A' 1785 1768        
5 A' 1719 1703        
6 A' 521 516        
7 A' 276 273        
8 A' 218 216        
9 A" 3581 3547        
10 A" 824 816        
11 A" 227 224        
12 A" 134 132        

Unscaled Zero Point Vibrational Energy (zpe) 9838.3 cm-1
Scaled (by 0.9906) Zero Point Vibrational Energy (zpe) 9745.8 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 CCSD(T)/3-21G
ABC
6.41251 0.22927 0.22896

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)/3-21G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.095 0.469 0.000
O2 0.006 1.462 0.000
O3 0.006 -1.360 0.000
H4 0.937 1.807 0.000
H5 -0.565 -1.546 0.792
H6 -0.565 -1.546 -0.792

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.99701.83111.58102.26352.2635
O20.99702.82210.99283.16273.1627
O31.83112.82213.30100.99430.9943
H41.58100.99283.30103.75863.7586
H52.26353.16270.99433.75861.5845
H62.26353.16270.99433.75861.5845

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 105.226 H1 O3 H5 102.396
H1 O3 H6 102.396 O2 H1 O3 172.121
H5 O3 H6 105.643
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability