Confinement and the CLOPW method
نویسنده
چکیده
Plane waves and Confined Localized Orbitals have been used to construct a new mixed basis for electronic structure calculations. Confinement is a mathematical transformation which smoothly suppresses the tails of the atomic orbitals. This eliminates multicentre integrals in the expressions for the matrix elements. Using self-consistent potentials supplied by the linear muffin tin orbital method (LMTO) we have calculated the bulk band structures of A1, Si, Cu, and LiH to a degree of accuracy comparable with the results given by the LMTO calculations. The basis functions are energy independent so the full solution is obtained without invoking any kind of linearization scheme.
منابع مشابه
Determination of Refractive Index and Confinement Losses in Photonic Crystal Fibers Using FDFD Method: A Comparative Analysis
In this paper, we present a comparative numerical analysis to determine the refractive index of photonic crystal fibers (PCFs) by using FDFD method and used the results to evaluate the confinement losses of PCFs by considering the effects of air-hole rings in the cladding. It is shown that by increasing the wavelength, the imaginary part of refraction index rises, resulting in increase of conf...
متن کاملNumerical Analysis of Index-Guiding Photonic Crystal Fibers with Low Confinement Loss and Ultra-Flattened Dispersion by FDFD Method
In this article, perfectly matched layer (PML) for the boundary treatment and an efficient compact two dimensional finite-difference frequency-domain (2-D FDFD) method were combined to model photonic crystal fibers (PCF). For photonic crystal fibers, if we assume that the propagation constant along the propagation direction is fixed, three-dimensional hybrid guided modes can be calculated by us...
متن کاملSADDLE POINT VARIATIONAL METHOD FOR DIRAC CONFINEMENT
A saddle point variational (SPV ) method was applied to the Dirac equation as an example of a fully relativistic equation with both negative and positive energy solutions. The effect of the negative energy states was mitigated by maximizing the energy with respect to a relevant parameter while at the same time minimizing it with respect to another parameter in the wave function. The Cornell pot...
متن کاملStudy of convergence confinement method curves considering pore-pressure effect
The design of underground spaces is mainly carried out using empirical, analytical, and numerical methods. The convergence confinement method (CCM) is an analytical technique that is widely utilized in analyzing the stability of underground spaces. However, the main challenge in the stability analysis is the selection of an accurate constitutive model for rock mass, and particularly, its post-f...
متن کاملCross Section Effects on Convergence-Confinement Method in Multi Stage Tunnel Excavation
Dimensionless coefficient () in convergence confinement method shows the relaxation of stress in the wall of the tunnel at different excavation movements. This factor is considered a constant number in previous studies and tunnel geometric characteristics (such as depth, cross-section shape, radius, soil material, etc.) are not included in its determination; however, ignoring these effects can...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003