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

using model chemistry: PBEPBE/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 PBEPBE/3-21G*
 hartrees
Energy at 0K-151.801629
Energy at 298.15K-151.805792
HF Energy-151.801629
Counterpoise corrected energy 
CP Energy at 298.15K 
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy38.903553
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 PBEPBE/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 3401 3243 25.41      
2 A 3399 3241 0.05      
3 A 3168 3020 234.46      
4 A 3073 2930 0.00      
5 A 1704 1624 75.28      
6 A 1664 1587 0.00      
7 A 1143 1090 0.00      
8 A 557 531 415.56      
9 A 478 456 0.00      
10 A 394 375 605.98      
11 A 319 304 0.00      
12 A 280 267 77.21      

Unscaled Zero Point Vibrational Energy (zpe) 9789.8 cm-1
Scaled (by 0.9535) Zero Point Vibrational Energy (zpe) 9334.6 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 PBEPBE/3-21G*
ABC
6.60195 0.28908 0.28482

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

Point Group is C1

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.362 0.052 -0.460
O2 1.265 0.123 0.036
O3 -1.256 -0.121 -0.047
H4 1.732 -0.742 -0.153
H5 -0.630 -0.174 0.750
H6 -1.531 0.848 -0.047

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H11.03231.67951.61331.58132.0951
O21.03232.53411.00102.04642.8896
O31.67952.53413.05451.01501.0066
H41.61331.00103.05452.59213.6318
H51.58132.04641.01502.59211.5780
H62.09512.88961.00663.63181.5780

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 105.009 H1 O3 H5 66.668
H1 O3 H6 99.456 O2 H1 O3 136.992
H5 O3 H6 102.620
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 H 0.303      
2 O -0.628      
3 O -0.628      
4 H 0.324      
5 H 0.303      
6 H 0.325      


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


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -13.890 -5.980 -1.553
y -5.980 -11.094 -0.118
z -1.553 -0.118 -12.409
Traceless
 xyz
x -2.139 -5.980 -1.553
y -5.980 2.056 -0.118
z -1.553 -0.118 0.083
Polar
3z2-r20.166
x2-y2-2.796
xy-5.980
xz-1.553
yz-0.118


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.448 -0.635 0.109
y -0.635 1.529 0.039
z 0.109 0.039 1.072


<r2> (average value of r2) Å2
<r2> 41.812
(<r2>)1/2 6.466