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arXiv · 2212.11786

An Improved Parameterization Procedure for NDDO-Descendant Semiempirical Methods

Adrian Wee Wen Ong·Steve Yueran Cao·Leong Chuan Kwek
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Abstract

MNDO-based semiempirical methods in quantum chemistry have found widespread application in the modelling of large and complex systems. A method for the analytic evaluation of first and second derivatives of molecular properties against semiempirical parameters in MNDO-based NDDO-descendant models is presented, and the resultant parameter Hessian is compared against the approximant currently used in parameterization for the PMx models. As a proof of concept, the exact parameter Hessian is employed in a limited reparameterization of MNDO for the elements C, H, N, O and F using 1206 molecules for reference data.

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Adrian Wee Wen Ong, Steve Yueran Cao, Leong Chuan Kwek. 2022-12-09. An Improved Parameterization Procedure for NDDO-Descendant Semiempirical Methods. https://arxiv.org/abs/2212.11786

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