Relativistic effects in many-electron

Needless to say, many-electron atoms and molecules are much more complicated than one-electron atoms, and the realization of the nonrelativistic limit is not easily accomplished in these cases because of the approximations needed for the description of a complicated many-particle system. However, the signature of relativistic effects (see, for example, Chapter 3 in this book) enables us to identify these effects even without calculation from experimental observation. Two mainly experimentally oriented chapters will report astounding examples of relativistic phenomenology, interpreted by means of the methods of relativistic electronic structure theory. These methods for the theoretical treatment of relativistic effects in many-electron atoms and molecules are the subject of most of the chapters in the present volume, and with the help of this theory relativistic effects can be characterized with high precision. 

Dzuba, V.A., Flambaum, V.V., and Webb, J.K., Calculations of the relativistic effects in many-electron atoms and space-time variation of fundamental constants, Phys. Rev. A, 59, 230, 1999 Space-time variation of physical constants and relativistic corrections in atoms, Phys. Rev. Lett., 82, 888, 1999. 

P. G. H. Sandars and J. Beck, Relativistic effects in many electron hyperfme structure. I. Theory, Proceedings of the Royal Society, 289, 97-107 (1965). 

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