x-P-T phase diagram for the. gamma. -. cap alpha. transition in Ce/sub 0. 9-x/La/sub x/Th/sub 0. 1/ alloys

Journal Article · Sun Apr 01 04:00:00 EST 1984 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.29.4017· OSTI ID:6828300

Lawrence, J M; Thompson, J D; Fisk, Z; Smith, J L; Batlogg, B

We report the results of resistivity measurements on Ce/sub 0.9-x/La/sub x/Th/sub 0.1/ alloys for x = 0.10, 0.11, 0.14, and 0.17 in the temperature interval 4.2--300 K and for the pressure range 0--12 kbar. Using these results we have semiquantitatively determined the P-T phase boundary for the isomorphic ..gamma..-..cap alpha.. phase transition for each concentration x. For x = 0.10, 0.11, and 0.14 the transitions are continuous at zero pressure, first order for pressures within the interval P/sub c//sup L/(x)P/sub c//sup u/(x). Hence, for these concentrations the phase boundaries terminate at two critical points. For x = 0.17, all observed transitions are continuous. Hence, in x-P-T space the surface of first-order transitions terminates at a critical edge (T/sub c/(x), P/sub c/(x)) such that, over an interval of x, P/sub c/(x) is double valued and such that there is a ''critical inflection point.'' These unusual features can be understood qualitatively as following from very general Fermi-liquid properties of the cerium 4f electronic system, together with the dilution and negative-pressure effects of alloying with lanthanum. We show that this qualitative description is consistent with existing experimental data.

• Research Organization: Center for Materials Science, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
• OSTI ID: 6828300
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 29:7; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
ACTINIDE ALLOYS
ALLOYS
CERIUM ALLOYS
CRITICAL TEMPERATURE
CRYSTAL-PHASE TRANSFORMATIONS
DIAGRAMS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
LANTHANUM ALLOYS
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
QUANTITY RATIO
RARE EARTH ALLOYS
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
THORIUM ALLOYS
TRANSITION TEMPERATURE