CHEM01200604005 A. K. Pathak - Homi Bhabha National Institute

P
7
P , , P , ,, 1 ∂
2 ∂ P
, ,,
1 6
∂
∂ P
, ,,
…………………
8
where, the averages of fluctuation of the number of solvent particles are defined as
P 0
P for m 1
9
9
In the homogeneous limit, one can write
P , ,
g i(r,ω); P , ,,
g i(r,ω)
10
where, ρ and ρ represent the ion and solvent density, respectively, and r r d r s .
Approximating the average density (=/V) to be equal to the solvent density, Eq.(6 ) can
be reduced to
g , g , , 1 ρ ∂
2 n ∂ρ ρg , ,
1
6
ρ
∂
∂ρ ρg , , .
11
The effect of a single ion on g , enters through the fluctuation of the number of
solvent particles and pair distribution g , , for the finite system. For simplicity, the
effect of a single ion on the fluctuation of the number of solvent particles is neglected.
This approximation is a reasonably good one if the system contains an appreciable
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