A uni ® ed review of Bloch operator modi ® ed Kohn variational methods
نویسنده
چکیده
A uni® ed review of various Kohn variational methods for scattering calculations is presented using appropriate Bloch operators. Previous expressions are generalized slightly to use either an in® nite range or a ® nite range of the scattering coordinate, or to use a basis set with non-® xed log derivative boundary conditions. A non-variationalmethod (method of moments) is used in the derivations; the results are con® rmed by Kohn variational derivations. Speculative linear variation functionals are introduced to connect both derivations. A model calculation of K (reactance) matrix is presented using a ® nite range and real algebra which is free of the so called `Kohn anomaly’ , unlike the conventional Kohn method for the K matrix.
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