atoms in solvent shell

Dear list:
Can someone suggest an easy way to obtain the list of atoms in a solvent shell (say 10A) around an irregular solute? I'm thinking of creating a compute to calculate the residence time of water molecules around a protein and wanted to exploit the efficiency of the lammps neighbor list to do this.

Any help would be appreciated.

Mike

Dear list:
Can someone suggest an easy way to obtain the list of atoms in a solvent shell (say 10A) around an irregular solute? I'm thinking of creating a compute to calculate the residence time of water molecules around a protein and wanted to exploit the efficiency of the lammps neighbor list to do this.

i don't know whether it is easy, but i would first look at the rdf compute.
that requires almost the same information, however, what you want to
do is a bit more ambitious and requires a bit more care. you'll need to
identify atoms by their tags for their history, and you have to consider
that the solute may be distributed across multiple domains and drift
around...

cheers,
    axel.

A compute could be written to do what you want, and computes
can use neighbor lists (see compute coord/atom for an example).

Something like:
compute 1 water nearest 10 protein

water = group of atoms to consider as candidate neighbors
protein = group of atoms to consider as central atoms
10 = cutoff distance

The the code could do a double loop and flag a list of atoms that
it finds.

loop I in protein group
  loop J over neighbors of I
    if I,J within delta and J in water group, flag_j = 1

and output a per-atom flag (0/1) for each atom, or the distances.

Steve