Towards a force field based on density fitting

A supervised fitting approach to force field parametrization with application to the SIBFA polarizable force field

A supervised, semiautomated approach to force field parameter fitting is described and applied to the SIBFA polarizable force field. The I-NoLLS interactive, nonlinear least squares fitting program is used as an engine for parameter refinement while keeping parameter values within a physical range. Interactive fitting is shown to avoid many of the stability problems that frequently afflict high...

3D Shape Estimation Based on Density Driven Model Fitting

We introduce a generic and efficient method for 2D and 3D shape estimation via density Þelds. Our method models shape as a density map and uses the notion of density to Þt a model to a rapidly computed occupancy map of the foreground object. We show how to utilize hierarchical (pyramid-like) object segmentation data to regularize a hierarchical model Þtting. With primary focus on estimating 3D ...

Smoothness-based forces for deformable models: a long-range force and a corner fitting force

Deformable models, originally proposed by Terzopoulos et al. (Artif. Intell. 36 (1988) 91) and Kass et al. (Int. J. Comput. Vision 1 (1988) 321) in 1988, have been widely used in medical image segmentation. However, they manifest two well-known limitations: the lack of an appropriate long-range force to drive the model surface towards the object boundary and poor performance at high curvature b...

Flexible Force Field Parameterization through Fitting on the Ab Initio-Derived Elastic Tensor

Constructing functional forms and their corresponding force field parameters for the metal-linker interface of metal-organic frameworks is challenging. We propose fitting these parameters on the elastic tensor, computed from ab initio density functional theory calculations. The advantage of this top-down approach is that it becomes evident if functional forms are missing when components of the ...

Status of the Gaussian Electrostatic Model, a Density-Based Polarizable Force Field