Liquid madelung energy and schottky defect energy related to liquid structure and melting temperature for alkali halides

Journal Article · Tue Jan 01 00:00:00 EST 1985 · J. Polym. Sci.; (United States)

DOI:https://doi.org/10.1016/0022-3697(85)90165-9· OSTI ID:6344219

March, N H; Tosi, M P

Motivated by the work of Reiss et al. in which the melting temperature T /SUB m/ of alkali halides is correlated with Coulomb energy, we consider the cohesive energy W of ionic melts and Schottky defect energy E /SUB s/ in the hot crystal, relative to the thermal energy k /SUB B/ T /SUB m/ . It is shown here that is accurately approximated by the liquid Madelung energy and hence that W/k /SUB B/ T /SUB m/ relates to the charge-charg direct correlation function c /SUB QQ/ (r) at r = 0. The existence of a ''Madelung constant'' for the liquid at T /SUB m/ is thereby demonstrated through the alkali halide series. An estimate of the ratio E /SUB s/ /k /SUB B/ T /SUB m/ i then considered; the basic additional ingredient being argued to be the static dielectric constant of the solid. Th BarrDawson-Lidiard empirical correlation between E /SUB s/ and k /SUB B/ T /SUB m/ can be understood in this way.

• Research Organization: Theoretical Chemistry Department, University of Oxford, Oxford
• OSTI ID: 6344219
• Journal Information: J. Polym. Sci.; (United States), Vol. 46:6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALKALI METAL COMPOUNDS
COULOMB ENERGY
MELTING POINTS
SCHOTTKY DEFECTS
HALIDES
BINDING ENERGY
CALCULATION METHODS
CORRELATION FUNCTIONS
CRYSTAL STRUCTURE
CRYSTALS
DIELECTRIC PROPERTIES
MELTING
CRYSTAL DEFECTS
ELECTRICAL PROPERTIES
ENERGY
FUNCTIONS
HALOGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
POINT DEFECTS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
VACANCIES
360104* - Metals & Alloys- Physical Properties