Slight adjustment to definition of Sinner and Dinner

doc/src/compute_sna_atom.rst

@@ -59,9 +59,9 @@ Syntax
        *bikflag* value = *0* or *1* (only implemented for compute snap)
           *0* = per-atom bispectrum descriptors are summed over atoms
           *1* = per-atom bispectrum descriptors are not summed over atoms
-       *switchinnerflag* values = *rinnerlist* *drinnerlist*
-          *rinnerlist* = *ntypes* values of rinner (distance units)
-          *drinnerlist* = *ntypes* values of drinner (distance units)
+       *switchinnerflag* values = *sinnerlist* *dinnerlist*
+          *sinnerlist* = *ntypes* values of *Sinner* (distance units)
+          *dinnerlist* = *ntypes* values of *Dinner* (distance units)
 
 Examples
 """"""""
@@ -316,21 +316,24 @@ The keyword *switchinnerflag* activates an additional radial switching
 function similar to :math:`f_c(r)` above, but acting to switch off
 smoothly contributions from neighbor atoms at short separation distances.
 This is useful when SNAP is used in combination with a simple
-repulsive potential. The keyword is followed by the *ntypes*
-values for :math:`r_{inner}` and the *ntypes*
-values for :math:`\Delta r_{inner}`. For a neighbor atom at
+repulsive potential. For a neighbor atom at
 distance :math:`r`, its contribution is scaled by a multiplicative
 factor :math:`f_{inner}(r)` defined as follows:
 
 .. math::
 
-               = & 0,  r \leq r_{inner} \\
-  f_{inner}(r) = & \frac{1}{2}(1 - \cos(\pi \frac{r-r_{inner}}{\Delta r_{inner}})), r_{inner} < r \leq r_{inner} + \Delta r_{inner} \\
-               = & 1,  r > r_{inner} + \Delta r_{inner}
+               = & 0,  r \leq S_{inner} - D_{inner} \\
+  f_{inner}(r) = & \frac{1}{2}(1 - \cos(\frac{\pi}{2} (1 + \frac{r-S_{inner}}{D_{inner}})), S_{inner} - D_{inner} < r \leq S_{inner} + D_{inner} \\
+               = & 1,  r > S_{inner} + D_{inner}
 
-The values of :math:`r_{inner}` and :math:`\Delta r_{inner}` are
-the arithmetic means of the values for the central atom of type I
-and the neighbor atom of type J.
+where the switching region is centered at :math:`S_{inner}` and it extends a distance :math:`D_{inner}`
+to the left and to the right of this.
+The keyword is followed by the *ntypes*
+values for :math:`S_{inner}` and the *ntypes*
+values for :math:`D_{inner}`. 
+When the central atom and the neighbor atom have different types,
+the values of :math:`S_{inner}` and :math:`D_{inner}` are
+the arithmetic means of the values for both types.
 
 .. note::
 
@@ -450,7 +453,7 @@ Default
 
 The optional keyword defaults are *rmin0* = 0,
 *switchflag* = 1, *bzeroflag* = 1, *quadraticflag* = 0,
-*bnormflag* = 0, *wselfallflag* = 0
+*bnormflag* = 0, *wselfallflag* = 0, *switchinnerflag* = off, 
 
 ----------
 

doc/src/pair_snap.rst

@@ -136,7 +136,7 @@ keyword/value pair. The required keywords are *rcutfac* and
 *twojmax*\ . Optional keywords are *rfac0*, *rmin0*,
 *switchflag*, *bzeroflag*, *quadraticflag*, *chemflag*,
 *bnormflag*, *wselfallflag*,  *switchinnerflag*,
-*rinner*, *drinner*, *chunksize*, and *parallelthresh*\ .
+*Sinner*, *Dinner*, *chunksize*, and *parallelthresh*\ .
 
 The default values for these keywords are
 
@@ -152,6 +152,9 @@ The default values for these keywords are
 * *chunksize* = 32768
 * *parallelthresh* = 8192
 
+For detailed definitions of all of these keywords,
+see the :doc:`compute sna/atom <compute_sna_atom>` doc page.
+
 If *quadraticflag* is set to 1, then the SNAP energy expression includes
 additional quadratic terms that have been shown to increase the overall
 accuracy of the potential without much increase in computational cost
@@ -194,7 +197,7 @@ pair_coeff command, to avoid ambiguity in the number of coefficients.
 The keyword *switchinnerflag* activates an additional switching function
 that smoothly turns off contributions to the SNAP potential from neighbor
 atoms at short separations. If *switchinnerflag* is set to 1 then
-the additional keywords *rinner* and *drinner* must also be provided.
+the additional keywords *Sinner* and *Dinner* must also be provided.
 Each of these is followed by *nelements* values, where *nelements*
 is the number of unique elements appearing in appearing in the LAMMPS
 pair_coeff command. The element order should correspond to the order
@@ -217,9 +220,6 @@ already large enough to saturate the GPU threads.  Extra parallelism
 will be performed if the *chunksize* (or total number of atoms per GPU)
 is smaller than *parallelthresh*.
 
-Detailed definitions for all the other keywords
-are given on the :doc:`compute sna/atom <compute_sna_atom>` doc page.
-
 .. note::
 
    The previously used *diagonalstyle* keyword was removed in 2019,