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

using model chemistry: HF/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/3-21G*
 hartrees
Energy at 0K-151.189403
Energy at 298.15K-151.192643
HF Energy-151.189403
Counterpoise corrected energy 
CP Energy at 298.15K 
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy37.227831
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 3528 53.79      
2 A' 3833 3460 4.93      
3 A' 3729 3366 286.70      
4 A' 1854 1673 99.41      
5 A' 1793 1618 100.44      
6 A' 490 442 120.39      
7 A' 245 221 100.30      
8 A' 201 181 355.92      
9 A" 3962 3576 45.68      
10 A" 832 751 273.05      
11 A" 205 185 7.53      
12 A" 151 137 232.59      

Unscaled Zero Point Vibrational Energy (zpe) 10601.3 cm-1
Scaled (by 0.9026) Zero Point Vibrational Energy (zpe) 9568.8 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 HF/3-21G*
ABC
7.15442 0.23101 0.23059

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
H10.97321.82581.56732.34092.3409
O20.97322.79730.96573.24813.2481
O31.82582.79733.26490.96650.9665
H41.56730.96573.26493.79993.7999
H52.34093.24810.96653.79991.5717
H62.34093.24810.96653.79991.5717

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 107.870 H1 O3 H5 110.083
H1 O3 H6 110.083 O2 H1 O3 175.795
H5 O3 H6 108.792
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 -3.510 0.000 3.512
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -10.814 6.888 0.000
y 6.888 -11.265 0.000
z 0.000 0.000 -10.642
Traceless
 xyz
x 0.139 6.888 0.000
y 6.888 -0.537 0.000
z 0.000 0.000 0.398
Polar
3z2-r20.796
x2-y20.451
xy6.888
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 1.080 0.489 0.000
y 0.489 1.393 0.000
z 0.000 0.000 1.071


<r2> (average value of r2) Å2
<r2> 49.627
(<r2>)1/2 7.045