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

using model chemistry: PBEPBEultrafine/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 PBEPBEultrafine/3-21G
 hartrees
Energy at 0K-151.801631
Energy at 298.15K-151.805812
HF Energy-151.801631
Counterpoise corrected energy-151.785559
CP Energy at 298.15K-151.788703
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy38.901011
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 PBEPBEultrafine/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 3370 25.75      
2 A 3398 3367 0.05      
3 A 3169 3140 233.94      
4 A 3074 3046 0.00      
5 A 1704 1688 75.39      
6 A 1665 1650 0.00      
7 A 1144 1134 0.00      
8 A 560 555 416.70      
9 A 481 477 0.00      
10 A 394 391 602.05      
11 A 319 316 0.00      
12 A 286 283 79.76      

Unscaled Zero Point Vibrational Energy (zpe) 9796.2 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 9707.0 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 PBEPBEultrafine/3-21G
ABC
6.60082 0.28902 0.28476

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

Point Group is C1

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.483 -0.022 -0.604
O2 1.298 0.132 0.017
O3 -1.289 -0.129 -0.030
H4 1.747 -0.767 0.073
H5 -0.532 0.011 0.657
H6 -1.770 0.759 -0.017

Atom - Atom Distances (Å)
  H1 O2 O3 H4 H5 H6
H11.03521.86541.61591.61872.4558
O21.03522.59981.00671.94183.1314
O31.86542.59983.10331.03211.0106
H41.61591.00673.10332.47733.8348
H51.61871.94181.03212.47731.5962
H62.45583.13141.01063.83481.5962

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 104.617 H1 O3 H5 60.011
H1 O3 H6 113.946 O2 H1 O3 124.863
H5 O3 H6 102.783
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBEultrafine/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 H 0.303      
2 O -0.628      
3 O -0.628      
4 H 0.325      
5 H 0.303      
6 H 0.324      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.001 0.000 -0.001 0.001
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -13.892 -5.980 -1.554
y -5.980 -11.093 -0.118
z -1.554 -0.118 -12.409
Traceless
 xyz
x -2.142 -5.980 -1.554
y -5.980 2.058 -0.118
z -1.554 -0.118 0.084
Polar
3z2-r20.168
x2-y2-2.799
xy-5.980
xz-1.554
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> 41.818
(<r2>)1/2 6.467