ev : list in the following form;
(define ev '(
5.0 ; max distance [nm] (or in the same dimension of "length")
( ; for EV type 1
0.0012 ; v [nm^3] (or in the same dimension of "length")
0 ; fene flag. if fene == 0, (p1,p2) = (A^{sp},L_{s})
1.0 ; p1 = A^{sp}, scaled spring const
2.1 ; p2 = L_{s} / length, scaled max extension
(0 1 2); list of particles belongs to the EV parameters
)
( ; for EV type 2
0.002 ; v [nm^3] (or in the same dimension of "length")
1 ; fene flag. if fene == 1, (p1,p2) = (N_{K,s},b_{K})
19.8 ; p1 = N_{K,s}, the Kuhn steps for a spring
106.0 ; p2 = b_{K} [nm], the Kuhn length
(3 4) ; list of particles belongs to the EV parameters
)
))
