It is shown how standard computer programs for calculating the equilibrium geometry of a molecule may be adapted to yield floating functions. These functions satisfy the Hellmann-Feynman theorem and so lead to simple electrostatic interpretations of intramolecular forces and vibrations. The theory i
Rapid and Accurate Computation of the Distance Function Using Grids
✍ Scribed by Yen-hsi Richard Tsai
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 409 KB
- Volume
- 178
- Category
- Article
- ISSN
- 0021-9991
No coin nor oath required. For personal study only.
✦ Synopsis
We present two fast and simple algorithms for approximating the distance function for given isolated points on uniform grids. The algorithms are then generalized to compute the distance to piecewise linear objects. By incorporating the geometry of Huygens' principle in the reverse order with the classical viscosity solution theory for the eikonal equation |∇u| = 1, the algorithms become almost purely algebraic and yield very accurate approximations. The generalized closest point formulation used in the second algorithm provides a framework for further extension to compute the distance accurately to smooth geometric objects on different grid geometries, without the construction of the Voronoi diagrams. This method provides a fast and simple translator of data commonly given in computational geometry to the volumetric representation used in level set methods.
📜 SIMILAR VOLUMES
In this paper, we present a technique, based on the principle of the frequency-domain con¨olution of a time-domain signature and a truncation window function, to process the electromagnetic field solution in a resonant structure deri¨ed by using the finite-difference ( ) time-domain FDTD algorithm.
## Abstract We present a new strategy to compute the impedance elements of the Magnetic‐Field Integral Equation (MFIE) formulation in Method of Moments (MoM) with a discretization of low‐order divergence‐conforming basis functions (RWG). The impedance matrix elements are accurately computed by swap
Optimized metal᎐ligand M᎐L bond lengths for 17 classical Werner-type transition-metal Ž . complexes were calculated using the local density approximation LDA and a gradient-Ž . ## corrected GC extension. GCs lengthen the bonds by between 0.02 and 0.09 A relative to ˚the LDA results. The latter ran