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

using model chemistry: HF_cp_opt/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_opt/3-21G
 hartrees
Energy at 0K-75.585943
Energy at 298.15K-75.588934
HF Energy-75.585943
Nuclear repulsion energy9.105114
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_cp_opt/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' 3906 3538 49.75      
2 A' 3836 3474 2.58      
3 A' 3735 3382 221.52      
4 A' 1844 1670 126.70      
5 A' 1806 1636 87.67      
6 A' 407 368 226.76      
7 A' 203 184 119.28      
8 A' 196 177 213.60      
9 A" 3969 3594 29.69      
10 A" 746 676 336.59      
11 A" 192 174 79.33      
12 A" 111 101 97.46      

Unscaled Zero Point Vibrational Energy (zpe) 10475.5 cm-1
Scaled (by 0.9056) Zero Point Vibrational Energy (zpe) 9486.6 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_cp_opt/3-21G
ABC
7.94298 0.21833 0.21734

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 -0.053 0.546 0.000
O2 -0.023 1.519 0.000
O3 -0.023 -1.344 0.000
H4 0.907 1.781 0.000
H5 -0.245 -1.863 0.783
H6 -0.245 -1.863 -0.783

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H10.97381.89011.56482.54012.5401
O20.97382.86320.96593.47873.4787
O31.89012.86323.26080.96570.9657
H41.56480.96593.26083.90163.9016
H52.54013.47870.96573.90161.5669
H62.54013.47870.96573.90161.5669

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 107.552 H1 O3 H5 122.238
H1 O3 H6 122.238 O2 H1 O3 177.280
H5 O3 H6 108.440
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF_cp_opt/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 H 0.000      
2 O 0.000      
3 O -0.726      
4 H 0.000      
5 H 0.363      
6 H 0.363      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.816 -4.459 0.000 4.533
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -6.564 1.844 0.000
y 1.844 0.276 0.000
z 0.000 0.000 -3.938
Traceless
 xyz
x -4.733 1.844 0.000
y 1.844 5.527 0.000
z 0.000 0.000 -0.794
Polar
3z2-r2-1.589
x2-y2-6.840
xy1.844
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 0.180 0.149 0.000
y 0.149 0.464 0.000
z 0.000 0.000 1.008


<r2> (average value of r2) Å2
<r2> 51.976
(<r2>)1/2 7.209