molecular
        weight          ??                  ?? -- Is it not used when calculating energy?
c       12.01         0.616               Sp2 C carbonyl group 
c1      12.01         0.360               Sp C
c2      12.01         0.360               Sp2 C  
c3      12.01         0.878               Sp3 C

Ebond = kr*(r-r0)^2
bond          kr       r0
ow-hw       553.0    0.9572      TIP3P water  
br-br       123.2    2.542        SOURCE1     4    0.0000    0.0000
br-c        240.3    1.946        SOURCE2     2    0.0285    0.0285

Eangle = kth*[(th-th0)*pi/180.0]^2
angle           kth        th0
hw-ow-hw        100.      104.52    TIP3P water
hw-hw-ow          0.      127.74    (found in crystallographic water with 3 bonds)
br-c -br         66.9     113.10    SOURCE0    1                  
br-c -c3         63.3     110.74    SOURCE3    1   0.0000   0.0000

I'm much confusing with this part. How to use these parameter to calcuate Etorsion?
Why the second column does not exist in certain torsion such as "c2-c3-c2-hc"? What
is the function of second column when calcuate Etorsion.  What is the meaning of positive
and negative n?

Etorsion = 0.5 * Vn * [ 1 + cos( n * phi - gamma ) ]       ---- ( I guess )
torsion         ??    Vn          gamma               n
X -c -c -X      4    1.200       180.000           2.000
X -c -c1-X      2    0.000       180.000           2.000     
X -c -cg-X      2    0.000       180.000           2.000      same as X-c-c1-X 
c3-c3-os-c      1    0.383         0.0            -3.         Junmei et al, 1999
c3-c3-os-c      1    0.80        180.0             1.         Junmei et al, 1999
c3-os-c3-os     1    0.10          0.0            -3.         Junmei et al, 1999
c2-c3-c2-hc          1.1         180.              2.         Junmei et al.1999
c2-c3-ca-hc          1.1         180.              2.         Junmei et al.1999
c2-hc-c -o           1.1         180.              2.         Junmei et al.1999

d = distance(i,j); a = d/(ri + rj);  Eab = sqrt(Ea*Eb);
Evdw = Eab*(1.0 / a^12 - 2.0 / a^6)
 vdw            r         E
  h1          1.3870  0.0157             Veenstra et al JCC,8,(1992),963 
  h2          1.2870  0.0157             Veenstra et al JCC,8,(1992),963 
  h3          1.1870  0.0157             Veenstra et al JCC,8,(1992),963