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ghcacj(金币+7): 谢谢 2011-02-16 13:05:09
In OPLS-AA, such nonbonded intramolecular interactions are described by the same parameters used in intermolecular
interactions, only scaled by a factor of 0.5.
这句话来自于文献：Molecular Force Field for Ionic Liquids Composed of Triflate or Bistriflylimide Anions
Jose´ N. Canongia Lopes, J. Phys. Chem. B 2004, 108, 16893-16898
当然不同的力场，定义1-4相互作用也不同。以下是以“charmm 1-4 interaction”在google中搜到的结果，也许对你有用：
LJ and electrostatic interactions between 1-4 neighbors are calculated, but can be modified compared to more distant pairs (different LJ interactions, scaling of electrostatic interactions). The details depend on the specific force field used. E.g., in the older polar hydrogen force field ("param19", electrostatic interactions and forces between 1-4 neighbors were scaled by 0.4, whereas in the current all-atom force field(s) ("param22", "param27", electrostatic energies and forces are used as is. This scaling factor is controlled by one of the many options to the ENERgy command, E14Fac. Thus, for calculations with the old, polar-hydrogen "param19" force field, E14Fac should be set to 0.4; for calculations with the current "param22/27" force field it should be set to 1.0.