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: HF_cp/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 HF_cp/3-21G
 hartrees
Energy at 0K-151.181491
Energy at 298.15K-151.174955
Nuclear repulsion energy 
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 HF/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' 3909 3540 53.71      
2 A' 3833 3471 4.95      
3 A' 3729 3377 287.25      
4 A' 1854 1679 99.41      
5 A' 1793 1623 100.45      
6 A' 490 444 120.32      
7 A' 245 222 99.55      
8 A' 201 182 356.74      
9 A" 3962 3588 45.70      
10 A" 832 753 273.06      
11 A" 205 185 7.62      
12 A" 151 137 232.46      

Unscaled Zero Point Vibrational Energy (zpe) 10601.5 cm-1
Scaled (by 0.9056) Zero Point Vibrational Energy (zpe) 9600.7 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 HF/3-21G
ABC
7.15484 0.23108 0.23066

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.045 0.490 0.000
O2 -0.001 1.462 0.000
O3 -0.001 -1.335 0.000
H4 0.903 1.802 0.000
H5 -0.464 -1.655 0.786
H6 -0.464 -1.655 -0.786

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.97321.82531.56732.34052.3405
O20.97322.79680.96573.24783.2478
O31.82532.79683.26450.96650.9665
H41.56730.96573.26453.79963.7996
H52.34053.24780.96653.79961.5717
H62.34053.24780.96653.79961.5717

picture of water dimer state 1 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 H 0.393      
2 O -0.802      
3 O -0.724      
4 H 0.345      
5 H 0.394      
6 H 0.394      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  -0.115 -3.511 0.000 3.513
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 0.000 0.000 0.000
y 0.000 0.000 0.000
z 0.000 0.000 0.000


<r2> (average value of r2) Å2
<r2> 49.614
(<r2>)1/2 7.044