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Water-Methane : Isotropic model with tetrahedral charge arrangement on water
Summary:
- 5 site charge model on water and ISA charges on methane for electrostatics. No damping.
- L1, isotropic undamped polarization model.
$C_{12}$, isotropic damped dispersion model.
- Isotropic exchange-repulsion terms only.
Units: Atomic Units
Citations
A. J. Misquitta & A. J. Stone, //Ab initio atom–atom potentials using CamCASP: Theory//
Geometry and charges
Source for water: Mulfit Source for methane: BS-ISA, A+DF $\zeta=0.1$ aug-cc-pVTZ main basis with aQZ/set2 aux basis. PBE0/AC. CamCASP 5.8.
<code | H2O_5site-tet.mom>
O 0.000000 0.000000 0.000000 Type O Rank 0
Q00 = -3.40282
H1 -1.453652 0.000000 -1.121687 Type H Rank 0
Q00 = 0.57768
H2 1.453652 0.000000 -1.121687 Type H Rank 0
Q00 = 0.57768
L1 0.000000 0.347336 0.245064 Type L Rank 0
Q00 = 1.12373
L2 0.000000 -0.347336 0.245064 Type L Rank 0
Q00 = 1.12373<code | CH4-ISA.mom>
! Based on DF-type : ISA
C 0.00000000 0.00000000 0.00000000 Type C Rank 0
-0.413530
H1 0.00000000 2.07703578 0.00000000 Type H Rank 0
0.103598
H2 1.69589261 -0.69234525 0.97912406 Type H Rank 0
0.103383
H3 -1.69589261 -0.69234525 0.97912406 Type H Rank 0
0.103383
H4 0.00000000 -0.69234525 -1.95824810 Type H Rank 0
0.103166
Polarizability
Source: Averaged terms taken from WSM L3,aniso; then multiplied by 0.9 for water (see water model and 1.08735 to better fit low-energy water-methane dimers. Main basis: d-aug-cc-pVTZ; Aux-basis: aug-cc-pVQZ. PBE0/AC with ALDA+CHF kernel. CamCASP 5.8.
H2O_daTZ_ref_wt4_L3_static-0_9averaged.pol
<code | H2O_daTZ_ref_wt4_L3_static-0_9averaged.pol> # Static polarizabilities O O 0.000 0.0000000 0.0000000 0.0000000 0.000 5.40801522 0.0000000 0.0000000 0.000 0.0000000 5.40801522 0.0000000 0.000 0.0000000 0.0000000 5.40801522 H1 H1 0.000 0.0000000 0.0000000 0.0000000 0.000 1.60741755 0.0000000 0.0000000 0.000 0.0000000 1.60741755 0.0000000 0.000 0.0000000 0.0000000 1.60741755 H2 H2 0.000 0.0000000 0.0000000 0.0000000 0.000 1.60741755 0.0000000 0.0000000 0.000 0.0000000 1.60741755 0.0000000 0.000 0.0000000 0.0000000 1.60741755
<code | CH4-averaged-scaled.pol> # Static polarizabilities C C 0.000 0.0000000 0.0000000 0.0000000 0.000 6.31667820135 0.0000000 0.0000000 0.000 0.0000000 6.31667820135 0.0000000 0.000 0.0000000 0.0000000 6.31667820135 H1 H1 0.000 0.0000000 0.0000000 0.0000000 0.000 3.19768616524 0.0000000 0.0000000 0.000 0.0000000 3.19768616524 0.0000000 0.000 0.0000000 0.0000000 3.19768616524 H2 H2 0.000 0.0000000 0.0000000 0.0000000 0.000 3.19768616524 0.0000000 0.0000000 0.000 0.0000000 3.19768616524 0.0000000 0.000 0.0000000 0.0000000 3.19768616524 H3 H3 0.000 0.0000000 0.0000000 0.0000000 0.000 3.19768616524 0.0000000 0.0000000 0.000 0.0000000 3.19768616524 0.0000000 0.000 0.0000000 0.0000000 3.19768616524 H4 H4 0.000 0.0000000 0.0000000 0.0000000 0.000 3.19768616524 0.0000000 0.0000000 0.000 0.0000000 3.19768616524 0.0000000 0.000 0.0000000 0.0000000 3.19768616524
Potential & Damping
Dispersion coefficients taken from $C_{12}$ anisotropic model. Tang-Toennies damping. Single dispersion damping coefficient, no induction damping.
<code| CH4-H2O-iso-tet.pot>
C O rho alpha
00 00 0 6.344866 1.744816
END
C HW rho alpha
00 00 0 4.250856 2.217943
END
H O rho alpha
00 00 0 4.712749 1.920271
END
H HW rho alpha
00 00 0 3.938414 1.705872
END
! Dispersion model
C O
Dispersion damping factor 1.88
End
C HW
Dispersion damping factor 1.88
End
H O
Dispersion damping factor 1.88
End
H HW
Dispersion damping factor 1.88
End
C O C6 C7 C8 C9 C10 C11 C12
00 00 0 16.88311 0.0 497.2595 0.0 24469.86 0.0 668674.5
End
C HW C6 C7 C8 C9 C10 C11 C12
00 00 0 4.753501 0.0 87.49391 0.0 4100.564
End
H O C6 C7 C8 C9 C10 C11 C12
00 00 0 7.994712 0.0 85.56545 0.0 1658.857
End
H HW C6 C7 C8 C9 C10 C11 C12
00 00 0 2.285648
End
Sample Orient command file
You will need the above files present in the directory as they are **included** into this Orient file.
Orient version: 4.7/4.8
<code | CH4-H2O-iso-tet.ornt>
UNITS BOHR
Parameters
Sites 20 polarizable 20
S-functions 50000
Alphas 50000
Parameter-sets 50000
Pairs 100000
End
Types
C Z 6
H Z 1
O Z 8
HW Z 1
L Z 0
End
Variables
Rx 0.0 B
Ry 0.0 B
Rz 0.0 B
alpha 0.0 D
Nx 0.0
Ny 0.0
Nz 0.0
Index 0
End
Molecule CH4 at 0.0 0.0 0.0 rotated by 0.0 about 1.0 0.0 0.0
#include CH4-ISA.mom
End
Polarizabilities for CH4
Read rank 1
#include CH4-averaged-scaled.pol
End
Limit rank 1 for C H1 H2 H3 H4
End
Molecule H2O at Rx Ry Rz ROTATED BY alpha ABOUT Nx Ny Nz
#include H2O_5site-tet.mom
End
Polarizabilities for H2O
Read rank 1
#include H2O_daTZ_ref_wt4_L3_static-0_9averaged.pol
End
Limit rank 1 for O H1 H2
End
Pairs
#include CH4-H2O-iso-tet.pot
End
Units Bohr kJ/mol
Switch Induce On Iterate On
Options
Induction Iterations 100
Convergence 1e-12
End
Energy Table Format f12.6 Print es er ind disp total
Variables
Index Rx Ry Rz alpha Nx Ny Nz
3 0.00000000 -5.23172000 0.10250400 152.84713000 0.68617877 -0.68617877 0.24148992
4 0.00000000 -5.55870250 0.10891050 152.84713000 0.68617877 -0.68617877 0.24148992
5 0.00000000 -5.88568500 0.11531700 152.84713000 0.68617877 -0.68617877 0.24148992
6 0.00000000 -6.21266750 0.12172350 152.84713000 0.68617877 -0.68617877 0.24148992
7 0.00000000 -6.40885700 0.12556740 152.84713000 0.68617877 -0.68617877 0.24148992
8 0.00000000 -6.53965000 0.12813000 152.84713000 0.68617877 -0.68617877 0.24148992
9 0.00000000 -6.67044300 0.13069260 152.84713000 0.68617877 -0.68617877 0.24148992
10 0.00000000 -6.86663250 0.13453650 152.84713000 0.68617877 -0.68617877 0.24148992
11 0.00000000 -7.19361500 0.14094300 152.84713000 0.68617877 -0.68617877 0.24148992
12 0.00000000 -7.52059750 0.14734950 152.84713000 0.68617877 -0.68617877 0.24148992
13 0.00000000 -7.84758000 0.15375600 152.84713000 0.68617877 -0.68617877 0.24148992
14 0.00000000 -8.50154500 0.16656900 152.84713000 0.68617877 -0.68617877 0.24148992
15 0.00000000 -9.15551000 0.17938200 152.84713000 0.68617877 -0.68617877 0.24148992
End
FinishOutput should end with
<code | end of output>
Rx Ry Rz alpha Nx Ny Nz Index es er ind disp total
3.00000 0.00000 -5.23172 0.10250 152.84713 0.68618 -0.68618 0.24149 -8.691824 63.526968 -8.404186 -27.479352 18.951606
4.00000 0.00000 -5.55870 0.10891 152.84713 0.68618 -0.68618 0.24149 -6.049812 35.918622 -5.010996 -19.249492 5.608322
5.00000 0.00000 -5.88568 0.11532 152.84713 0.68618 -0.68618 0.24149 -4.296750 20.379915 -3.138842 -13.540474 -0.596151
6.00000 0.00000 -6.21267 0.12172 152.84713 0.68618 -0.68618 0.24149 -3.108953 11.595261 -2.042047 -9.579946 -3.135685
7.00000 0.00000 -6.40886 0.12557 152.84713 0.68618 -0.68618 0.24149 -2.581664 8.275468 -1.601726 -7.810300 -3.718222
8.00000 0.00000 -6.53965 0.12813 152.84713 0.68618 -0.68618 0.24149 -2.288268 6.611479 -1.369867 -6.826881 -3.873536
9.00000 0.00000 -6.67044 0.13069 152.84713 0.68618 -0.68618 0.24149 -2.033305 5.283508 -1.176393 -5.975322 -3.901512
10.00000 0.00000 -6.86663 0.13454 152.84713 0.68618 -0.68618 0.24149 -1.710830 3.776198 -0.942928 -4.905996 -3.783556
11.00000 0.00000 -7.19362 0.14094 152.84713 0.68618 -0.68618 0.24149 -1.297638 2.159675 -0.663633 -3.558695 -3.360291
12.00000 0.00000 -7.52060 0.14735 152.84713 0.68618 -0.68618 0.24149 -0.997328 1.236433 -0.476274 -2.607489 -2.844657
13.00000 0.00000 -7.84758 0.15376 152.84713 0.68618 -0.68618 0.24149 -0.775887 0.708432 -0.347805 -1.930770 -2.346030
14.00000 0.00000 -8.50155 0.16657 152.84713 0.68618 -0.68618 0.24149 -0.485209 0.232956 -0.194102 -1.093547 -1.539902
15.00000 0.00000 -9.15551 0.17938 152.84713 0.68618 -0.68618 0.24149 -0.315273 0.076705 -0.114083 -0.646459 -0.999110