使用期限*
许可形式单机
原产地奥地利
介质下载
适用平台windows
科学软件网提供软件和培训服务已有19年,拥有丰富的经验,提供软件产品上千款,涵盖领域包括经管,仿真,地球地理,生物化学,工程科学,排版及网络管理等。同时还有的服务,现场培训+课程,以及本地化服务。
where ul(r,El) is the (at the origin) regular solution of the radial Schroedinger equation for energy El (chosen normally at the center of the corresponding band with l-like character) and the spherical part of the potential inside sphere t $\dot u_l(r,E_l)$ is the energy derivative of ul taken at the same energy El. A linear combination of these two functions constitute the linearization of the radial function; the coefficients Alm and Blm are functions of kn (see below) determined by requiring that this basis function matches (in value and slope) the corresponding basis function of the interstitial region; $u_l$ and $\dot u_l$ are obtained by numerical integration of the radial Schroedinger equation on a radial mesh inside the sphere.
The APW+lo method
Sjöstedt, Nordström and Singh (2000) have shown that the standard LAPW method with the additional constraint on the PWs of matching in value AND slope to the solution inside the sphere is not the most efficient way to linearize Slater's APW method. It can be made much more efficient when one uses the standard APW basis, but of course with ul(r,El) at a fixed energy El in order to keep the linear eigenvalue problem. One then adds a new local orbital (lo) to have enough variational flexibility in the radial basisfunctions:
and the coefficients cn are determined by the Rayleigh-Ritz variational principle. The convergence of this basis set is controlled by a cutoff parameter RmtKmax= 6 - 9, where Rmt is the smallest atomic sphere radius in the unit cell and Kmax is the magnitude of the largest K vector.
The Fermi energy and the weights of each band state can be calculated using a modified tetrahedron method (Bloechl et al. 94), a Gaussian or a temperature broadening scheme.
科学软件网不定期举办各类公益培训和讲座,让您有更多机会免费学习和熟悉软件。
http://turntech8843.b2b168.com