Muffin-tin approximation Muffin-tin approximation The muffin-tin approximation is a shape approximation of the potential well in an crystal lattice. It is most commonly employed in quantum mechanical simulations of the electronic band structure in solids. The approximation was proposed by John C. Slater. Augmented plane wave method (APW) is a method which uses muffin-tin approximation. It is a method to approximate the energy states of an electron in a crystal lattice. The basic approximation lies in the potential in which the potential is assumed to be spherically symmetric in the muffin-tin region and constant in the interstitial region. Wave functions (the augmented
Wedding customs by country weddings in the United States follow a similar pattern to an English wedding. It traditionally follows the "white wedding" type (see also "Wedding types" below), which originates from the white color of the bride's wedding dress, but refers to an entire wedding routine. Customs and traditions vary, but common components are listed below. The purpose of inviting guests is to have them witness a couple's marriage ceremony and vows and to share in their joy and celebration. Gifts for the wedding couple are optional, although most guests attempt to give at least a token gift of their best wishes. Some