Drude oscillator model

Vorobyov IV, VM Anisimov, AD MacKerell Jr (2005) Polarizable empirical force field for alkanes based on the classical drude oscillator model. J. Phys. Chem. B 109 (40) 18988-18999... 

Explicit Inclusion of Induced Polarization in Atomistic Force Fields Based on the Classical Drude Oscillator Model... 

The Drude oscillator model has a number of advantages over other polarizable models facilitating its implementation in multiple simulation packages including CHARMM [150], NAMD [165], ChemSell QM/MM [192] and the OpenMM suite of utilities for GPU [193]. Representing a dipole as two point charges provides an intuitive physical picture in terms of displacement of the electronic distribution the model is able to represent delocalization without need of additional non-atomic sites since the dipole is not point-like as, e.g., in the induced dipole model. For example, the use of auxiliary particles allows for the inclusion of mechanical polarizabilities [194]... 

Savelyev, A., and A. D. MacKerell, All-atom polarizable force field for DNA based on the classical drude oscillator model/. Comput. Chem., 2014. 35(16), 1219-1239. 

Lemkul, J. A., Roux, B., van der Spoel, D and MacKerell, A. D., Jr., Implementation of Extended Lagrangian Dynamics in GROMACS for Polarizable Simulations Using the Classical Drude Oscillator Model, In Press./ Comput. Chem., 2015. 36,1480-1486. 

In the Drude oscillator model, the polarization effect is described by a point charge (the Drude oscillator) attached to each nonhydrogen atom via a harmonic spring. The point charge can move relative to the attachment site in response to the electrostatic environment. The electrostatic energy is the sum of the pairwise interactions between atomic charges and the partial charge of the Drude particles... 

T. Sommerfeld and K. D. Jordan, /. Phys. Chem. A, 109, 11531-11538 (2005). Quantum Drude Oscillator Model for Describing the Interaction of Excess Electrons with Water Clusters An Application to (H20)jj. 

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