1.. index:: pair_style born/coul/dsf/cs 2.. index:: pair_style born/coul/long/cs 3.. index:: pair_style born/coul/long/cs/gpu 4.. index:: pair_style born/coul/wolf/cs 5.. index:: pair_style born/coul/wolf/cs/gpu 6.. index:: pair_style buck/coul/long/cs 7.. index:: pair_style coul/long/cs 8.. index:: pair_style coul/long/cs/gpu 9.. index:: pair_style coul/wolf/cs 10.. index:: pair_style lj/cut/coul/long/cs 11.. index:: pair_style lj/class2/coul/long/cs 12 13pair_style born/coul/dsf/cs command 14=================================== 15 16pair_style born/coul/long/cs command 17==================================== 18 19Accelerator Variants: *born/coul/long/cs/gpu* 20 21pair_style born/coul/wolf/cs command 22==================================== 23 24Accelerator Variants: *born/coul/wolf/cs/gpu* 25 26pair_style buck/coul/long/cs command 27==================================== 28 29pair_style coul/long/cs command 30=============================== 31 32Accelerator Variants: *coul/long/cs/gpu* 33 34pair_style coul/wolf/cs command 35=============================== 36 37pair_style lj/cut/coul/long/cs command 38====================================== 39 40pair_style lj/class2/coul/long/cs command 41========================================= 42 43Syntax 44"""""" 45 46.. code-block:: LAMMPS 47 48 pair_style style args 49 50* style = *born/coul/dsf/cs* or *born/coul/long/cs* or *born/coul/wolf/cs* or *buck/coul/long/cs* or *coul/long/cs* or *coul/wolf/cs* or *lj/cut/coul/long/cs* or *lj/class2/coul/long/cs* 51* args = list of arguments for a particular style 52 53.. parsed-literal:: 54 55 *born/coul/dsf/cs* args = alpha cutoff (cutoff2) 56 alpha = damping parameter (inverse distance units) 57 cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units) 58 cutoff2 = global cutoff for Coulombic (distance units) 59 *born/coul/long/cs* args = cutoff (cutoff2) 60 cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units) 61 cutoff2 = global cutoff for Coulombic (optional) (distance units) 62 *born/coul/wolf/cs* args = alpha cutoff (cutoff2) 63 alpha = damping parameter (inverse distance units) 64 cutoff = global cutoff for Buckingham (and Coulombic if only 1 arg) (distance units) 65 cutoff2 = global cutoff for Coulombic (optional) (distance units) 66 *buck/coul/long/cs* args = cutoff (cutoff2) 67 cutoff = global cutoff for Buckingham (and Coulombic if only 1 arg) (distance units) 68 cutoff2 = global cutoff for Coulombic (optional) (distance units) 69 *coul/long* args = cutoff 70 cutoff = global cutoff for Coulombic (distance units) 71 *coul/wolf* args = alpha cutoff 72 alpha = damping parameter (inverse distance units) 73 cutoff = global cutoff for Coulombic (distance units) 74 *lj/cut/coul/long/cs* args = cutoff (cutoff2) 75 cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units) 76 cutoff2 = global cutoff for Coulombic (optional) (distance units) 77 *lj/class2/coul/long/cs* args = cutoff (cutoff2) 78 cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units) 79 cutoff2 = global cutoff for Coulombic (optional) (distance units) 80 81Examples 82"""""""" 83 84.. code-block:: LAMMPS 85 86 pair_style born/coul/dsf/cs 0.1 10.0 12.0 87 pair_coeff * * 0.0 1.00 0.00 0.00 0.00 88 pair_coeff 1 1 480.0 0.25 0.00 1.05 0.50 89 90 pair_style born/coul/long/cs 10.0 8.0 91 pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51 92 93 pair_style born/coul/wolf/cs 0.25 10.0 12.0 94 pair_coeff * * 0.0 1.00 0.00 0.00 0.00 95 pair_coeff 1 1 480.0 0.25 0.00 1.05 0.50 96 97 pair_style buck/coul/long/cs 10.0 98 pair_style buck/coul/long/cs 10.0 8.0 99 pair_coeff * * 100.0 1.5 200.0 100 pair_coeff 1 1 100.0 1.5 200.0 9.0 101 102 pair_style coul/long/cs 10.0 103 pair_coeff * * 104 105 pair_style coul/wolf/cs 0.2 9.0 106 pair_coeff * * 107 108 pair_style lj/cut/coul/long/cs 10.0 109 pair_style lj/cut/coul/long/cs 10.0 8.0 110 pair_coeff * * 100.0 3.0 111 pair_coeff 1 1 100.0 3.5 9.0 112 113Description 114""""""""""" 115 116These pair styles are designed to be used with the adiabatic 117core/shell model of :ref:`(Mitchell and Finchham) <MitchellFinchham2>`. See 118the :doc:`Howto coreshell <Howto_coreshell>` page for an overview of 119the model as implemented in LAMMPS. 120 121All the styles are identical to the corresponding pair style without 122the "/cs" in the name: 123 124* :doc:`pair_style born/coul/dsf <pair_born>` 125* :doc:`pair_style born/coul/long <pair_born>` 126* :doc:`pair_style born/coul/wolf <pair_born>` 127* :doc:`pair_style buck/coul/long <pair_buck>` 128* :doc:`pair_style coul/long <pair_coul>` 129* :doc:`pair_style coul/wolf <pair_coul>` 130* :doc:`pair_style lj/cut/coul/long <pair_lj_cut_coul>` 131* :doc:`pair_style lj/class2/coul/long <pair_class2>` 132 133except that they correctly treat the special case where the distance 134between two charged core and shell atoms in the same core/shell pair 135approach r = 0.0. 136 137Styles with a "/long" in the name are used with a long-range solver 138for Coulombic interactions via the :doc:`kspace_style <kspace_style>` 139command. They require special treatment of the short-range Coulombic 140interactions within the cor/shell model. 141 142Specifically, the short-range Coulomb interaction between a core and 143its shell should be turned off using the 144:doc:`special_bonds <special_bonds>` command by setting the 1-2 weight 145to 0.0, which works because the core and shell atoms are bonded to 146each other. This induces a long-range correction approximation which 147fails at small distances (~< 10e-8). Therefore, the Coulomb term which 148is used to calculate the correction factor is extended by a minimal 149distance (r_min = 1.0-6) when the interaction between a core/shell 150pair is treated, as follows 151 152.. math:: 153 154 E = \frac{C q_i q_j}{\epsilon (r + r_{min})} \qquad r \rightarrow 0 155 156where C is an energy-conversion constant, :math:`q_i` and :math:`q_j` 157are the charges on the core and shell, epsilon is the dielectric 158constant and :math:`r_{min}` is the minimal distance. 159 160For styles that are not used with a long-range solver, i.e. those with 161"/dsf" or "/wolf" in the name, the only correction is the addition of 162a minimal distance to avoid the possible r = 0.0 case for a core/shell 163pair. 164 165---------- 166 167.. include:: accel_styles.rst 168 169---------- 170 171Mixing, shift, table, tail correction, restart, rRESPA info 172""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 173 174See the corresponding doc pages for pair styles without the "cs" 175suffix to see how mixing, shifting, tabulation, tail correction, 176restarting, and rRESPA are handled by theses pair styles. 177 178---------- 179 180Restrictions 181"""""""""""" 182 183These pair styles are part of the CORESHELL package. They are only 184enabled if LAMMPS was built with that package. See the :doc:`Build package <Build_package>` page for more info. 185 186Related commands 187"""""""""""""""" 188 189:doc:`pair_coeff <pair_coeff>`, :doc:`pair_style born <pair_born>`, 190:doc:`pair_style buck <pair_buck>` 191 192Default 193""""""" 194 195none 196 197---------- 198 199.. _MitchellFinchham2: 200 201**(Mitchell and Finchham)** Mitchell, Finchham, J Phys Condensed Matter, 2025, 1031-1038 (1993). 203