FIXME: need some  minimal documentation --- I myself  forget the basic
usage after a couple of weeks.

Example usage:

a) Compute  solvation energy  by 1D-RISM specifying  the names  of the
solvent  and  solute  molecules  to  be  picked  from  the  hard-wired
database:

  ./guile/runbgy.scm energy \
    --norm-tol 1e-14 --dielectric 78.4 \
    --rho 0.0333295 --beta 1.6889 \
    --L 160 --N 4096 \
    --solvent "water, PR-SPC/E" --solute "water, PR-SPC/E"

This should give a number close to -7.869294 kcal.

b) Compute solvation energy by 3D-RISM for solute and solvent from the
database using the solvent susceptibility from a 1D-RISM calculation:

  mpiexec -n 8 ./guile/runbgy.scm energy \
    --norm-tol 1e-14 --dielectric 78.4 \
    --rho 0.0333295 --beta 1.6889 \
    --L 10 --N 96 \
    --solvent "water, PR-SPC/E" --solute "water, PR-SPC/E" \
    --hnc

This should  give you a number  close to -6.349052 kcal  (look for the
"mu  ="  lines in  the  output). If  you  supply  --no-renorm flag  in
addition you  should get  -6.297170 kcal as  in earlier  versions. For
solutes without charged sites there should be no visible difference.

c) Compute self-interaction energy of an MM solute:

  ./guile/runbgy.scm self-energy "uranyl, 5w, pcm"