Antisymmetry in the quantum Monte Carlo method without a trial function

✍ Scribed by R. Bianchi; D. Bressanini; P. Cremaschi; G. Morosi

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 288 KB
• Volume: 184
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(91)85134-i

✦ Synopsis

The problem of antisymmetry in the quantum Monte Carlo method is handled by a technique able to build up mobile nodal surfaces, self-adapting to the signed psip distribution. We define a function A as a sum of Gaussians, each one centered on a psip and with its own sign. This sum is extended to the psips obtained by antisymmetrization of those actually used in the random walk. The A function defines the nodal surfaces in the full (3N-I)-dimensional space and not only in the (3N-3)-dimensional subspace obtained by the antisymmetry definition. Calculations are presented for the 2P state of the hydrogen atom and for the triplet state of the hydrogen molecule.