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Is the sigma-value in Lennard-Jones potential formula equivalent...
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Kolade Emmanuel Omolagba
Is the sigma-value in Lennard-Jones potential formula equivalent...
These articles can be useful:
1. https://doi.org/10.1088/0959-5309/43/5/301 (L.Jones / Cohesion (1931)) "[...]In each case the potential of the attractive field is of the form -lR^- 6 , and the values obtained for l are as follows :[...]"
2. https://doi.org/10.1103/PhysRev.37.682 (Slater-Kirdwood / The Van Der Waals Forces in Gases (1931)) "[...] A correlation between the mutual energy of the two molecules, e, and the polarizability, cx, is obtained: —1.36 vp ap a3 Ep/R^6 [...]"
1. https://doi.org/10.1088/0959-5309/43/5/301 (L.Jones / Cohesion (1931)) "[...]In each case the potential of the attractive field is of the form -lR^- 6 , and the values obtained for l are as follows :[...]"
2. https://doi.org/10.1103/PhysRev.37.682 (Slater-Kirdwood / The Van Der Waals Forces in Gases (1931)) "[...] A correlation between the mutual energy of the two molecules, e, and the polarizability, cx, is obtained: —1.36 vp ap a3 Ep/R^6 [...]"
The van der Waals radius is itself an approximation of a sort, since atoms are not hard spheres in reality. Different experimental methods of estimation yield different values for the same species. One could say the LJ sigma parameter is in the same order of magnitude as the vdW radius, but sigma should be picked to produce the desired interatomic distance or some other property in the simulation, rather than precisely equal to the vdW radius.
The van der Waals radius is itself an approximation of a sort, since atoms are not hard spheres in reality. Different experimental methods of estimation yield different values for the same species. One could say the LJ sigma parameter is in the same order of magnitude as the vdW radius, but sigma should be picked to produce the desired interatomic distance or some other property in the simulation, rather than precisely equal to the vdW radius.
These articles can be useful:
1. https://doi.org/10.1088/0959-5309/43/5/301 (L.Jones / Cohesion (1931))
"[...]In each case the potential of the attractive field is of the form -lR^- 6 , and the values obtained for l are as follows :[...]"
2. https://doi.org/10.1103/PhysRev.37.682 (Slater-Kirdwood / The Van Der Waals Forces in Gases (1931))
"[...] A correlation between the mutual energy of the two molecules, e, and the polarizability, cx, is obtained: —1.36 vp ap a3 Ep/R^6 [...]"
These articles can be useful:
1. https://doi.org/10.1088/0959-5309/43/5/301 (L.Jones / Cohesion (1931))
"[...]In each case the potential of the attractive field is of the form -lR^- 6 , and the values obtained for l are as follows :[...]"
2. https://doi.org/10.1103/PhysRev.37.682 (Slater-Kirdwood / The Van Der Waals Forces in Gases (1931))
"[...] A correlation between the mutual energy of the two molecules, e, and the polarizability, cx, is obtained: —1.36 vp ap a3 Ep/R^6 [...]"
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To Asdrubal Lozada :
Thanks for the reading material, especially the ref.1, very easy to read and understandable.
To Jyri Kimari :
Thanks for the clarification about that sigma parameter should not be arbitrarily correlated to vdW radius.
To Asdrubal Lozada :
Thanks for the reading material, especially the ref.1, very easy to read and understandable.
To Jyri Kimari :
Thanks for the clarification about that sigma parameter should not be arbitrarily correlated to vdW radius.
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The van der Waals radius is itself an approximation of a sort, since atoms are not hard spheres in reality. Different experimental methods of estimation yield different values for the same species. One could say the LJ sigma parameter is in the same order of magnitude as the vdW radius, but sigma should be picked to produce the desired interatomic distance or some other property in the simulation, rather than precisely equal to the vdW radius.
The van der Waals radius is itself an approximation of a sort, since atoms are not hard spheres in reality. Different experimental methods of estimation yield different values for the same species. One could say the LJ sigma parameter is in the same order of magnitude as the vdW radius, but sigma should be picked to produce the desired interatomic distance or some other property in the simulation, rather than precisely equal to the vdW radius.
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