English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The aim of this paper is to present a procedure for determining the power series in N-1/Z for the approximate energy levels and eigenspaces of the nonrelativistic Hamiltonians H-(N,H-Z) with N-electrons and nuclear charge Z. To this effect the theory of the best multiconfigurational approximations is applied.

A Method of Solving the Eigenproblem of the Atomic Ion Hamiltonians. I. Theory