| MAME water model: Coulomb, induction and dispersion interactions in water dimer | ||
| Eugene V. Tsiper, George Mason University and Naval Research Lab, Washington, DC The Minimal Atomic Multipole Expansion (MAME) substitutes the ab-initio or DFT density with the minimal set of atomic multipoles, which eliminates redundancies and reproduces molecular electrostatic potential everywhere beyond the molecular volume. We apply MAME ideas to construct a new polarizable water model, which appears to be transparent, intuitive and accurate at the same time. Hydrogen bonding, electrostatic, induction and dispersion interactions in the water dimer are reproduced by only three multipoles μ(H), μ(O) and θ(O) and two polarizabilities α(O) and α(H), which characterize a single water molecule and can be deduced either from single-molecule data or from DFT MAME calculation. The model agrees with the two best water pair potentials, VRT(ASP-W)III and SAPT-5s, and compares favorably to popular water models, such as TIP4P-FQ.
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