$$E_{bond} = D_e\left[1 - e^{-a(r-r_0)}\right]^2$$
Morse势:\(D_e\) 键离解能,\(r_0\) 平衡键距
$$E_{total} = \sum E_{bond} + \sum E_{angle} + \sum E_{torsion} + \sum E_{vdW}$$
分子力场(MMFF/UFF):键、角、二面角、范德华势之和
$$\text{IHD} = \frac{2C + 2 + N - H - X}{2}$$
不饱和度(IHD):\(C, N, H, X\) 为各元素原子数。环或双键各+1