Shifted homologous relationships between the transplutonium and early rare-earth metals

Conference · Sun Jan 01 04:00:00 EST 1984

DOI:https://doi.org/10.1007/978-94-009-5444-1_12· OSTI ID:6364852

Ward, J W

The physico-chemical properties of the late actinide metals americium through einsteinium are compared with their rare-earth counterparts. Localization of the 5f electrons beginning at americium signals the appearance of true rare-earth-like properties, but the homologous relationship is shifted to place americium below praseodymium, einsteinium then below europium. The comparison of crystal structure, phase transitions, vapor pressures and heats of vaporization reveals remarkable similarities, especially for Sm-Cf and Eu-Es, where the stability of the divalent metal becomes established and divalent chemistry then follows. There is of course a major perturbation at the half-filled shell at curium, and it may be argued that americium is the anomaly in the so-called second rare-earth series. However, the response of americium, berkelium and californium under pressure reveals the true perturbation to be a thermodynamic one, occurring at curium.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6364852
• Report Number(s): LA-UR-85-242; CONF-841229-2; ON: DE85006712
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400702 -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
COMPARATIVE EVALUATIONS
ELECTRONIC STRUCTURE
ELEMENTS
METALS
RARE EARTHS
TRANSPLUTONIUM ELEMENTS
TRANSURANIUM ELEMENTS