Solvation calculation in Gaussian 94

 Dear CCL users,
 I was trying to use G94 to do some solvation calculations and
 had difficulty in understanding the meanings of some of the
 output lines. I appreciate any of your help.
 In the input file, I wrote
 #T rhf/6-31g(d) scrf=ipcm volume test
 The output due to the keyword "volume" are
  Box volume = 2398.137 fraction occupied=1.000
  Molar volume = 2398.137 bohr**3/mol (214.007 cm**3/mol)
  Recommended a0 for SCRF calculation =  5.34 angstrom ( 10.08 bohr)
 Question (1): What's the shape of the box?
 Question (2): How to calculate a0 from the molar volume?
               It seems to me that the formula
               (molar volume/Pi)^(1/3)+0.94 bohr
               is used. But why?
 The some of the output due to scrf=ipcm are
  Max. Dist. Between Center of Nuclear Charge and Isosurface = 5.222190E+00
  Min. Dist. Between Center of Nuclear Charge and Isosurface = 3.402845E+00
  Total "Solvent Accessible Surface Area" of Solute = 2.467157E+02
  Volume of Solute Cavity = 3.391144E+02
 Question (3): What are the units of these values?
 Question (4): Where can I find references that explains how to calculate
               these values?
 Thank you.
 Shiang-Tai
 Department of Chemical Engineering
 University of Delaware
 (O) (302) 831-6857
 (H) (302) 368-8388
 E-mail: stlin "at@at" udel.edu