Table 2: The intermolecular potential parameters of the NC chain.

Harmonic bonds: U(r) = k(rr0 )2/2
Bonds
O – H
k
300
r0
1.724
Valence angles: U(θ) = k(θθ0 )2/2
Bonds
O-P-O
P-O-C
C-O-C
N-C-N
N-C-C
N-C-H
C-N-C
k
100.33
106.70
106.70
133.33
133.33
133.33
133.33
θ0
93.300
104.510
104.510
120.000
120.000
120.000
120.000
Bonds
C-N*-C
C-N-H
O-C-H
H-C-H
O-C-C
H-C-C
C-C-C
k
109.00
109.00
112.50
112.50
112.50
112.50
112.50
θ0
106.700
106.700
109.471
109.471
109.471
109.471
109.471
Dihedral angles: U(φ) = A[1+cos(mφδ)]
Bonds
P-O-C-H
P-O-C-C
C-O-C-H
C-O-C-N
C-O-C-C
C-O-P-O
C-N-C-C
N-C-C-O
N-C-C-N
C-C-C-O
C-C-C-N
C-N-C-N
H-C-N-C
N-C-N-C
N-C-C-H
N-C-C-C
H-C-C-H
H-C-C-C
A
0.3333
0.3333
0.3333
0.3333
0.3333
0.5000
2.5000
2.5000
2.5000
2.5000
2.5000
2.5000
11.250
11.250
5.6250
5.6250
5.6250
5.6250
δ
0
0
0
0
0
0
180
180
180
180
180
180
180
180
180
180
180
180
m
3
3
3
3
3
3
2
2
2
2
2
2
2
2
2
2
2
2