The origin of the conductivity maximum in molten salts. II. SnCl2 and HgBr2

被引:15
作者
Aravindakshan, Nikhil P. [1 ]
Kuntz, Colin M. [1 ]
Gemmell, Kyle E. [1 ]
Johnson, Keith E. [1 ]
East, Allan L. L. [1 ]
机构
[1] Univ Regina, Dept Chem & Biochem, Regina, SK S4S 0A2, Canada
基金
加拿大创新基金会; 加拿大自然科学与工程研究理事会;
关键词
ELECTRICAL CONDUCTANCE; ULTRASOFT PSEUDOPOTENTIALS; PHYSICAL-PROPERTIES; MOLECULAR-DYNAMICS; LIQUID IODINE; TEMPERATURE; TRANSPORT; TRANSITION; ELECTRODEPOSITION; ELECTROLYTES;
D O I
10.1063/1.4961687
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The phenomenon of electrical conductivity maxima of molten salts versus temperature during orthobaric (closed-vessel) conditions is further examined via ab initio simulations. Previously, in a study of molten BiCl3, a new theory was offered in which the conductivity falloff at high temperatures is due not to traditional ion association, but to a rise in the activation energy for atomic ions hopping from counterion to counterion. Here this theory is further tested on two more inorganic melts which exhibit conductivity maxima: another high-conducting melt (SnCl2, s(max) = 2.81 Omega(-1) cm(-1)) and a low-conducting one (HgBr2, sigma max = 4.06 x 10(-4) Omega(-1) cm(-1)). First, ab initio molecular dynamics simulations were performed and again appear successful in reproducing the maxima for both these liquids. Second, analysis of the simulated liquid structure (radial distributions, species concentrations) was performed. In the HgBr2 case, a very molecular liquid like water, a clear Grotthuss chain of bromide transfers was observed in simulation when seeding the system with a HgBr+ cation and HgBr3-anion. The first conclusion is that the hopping mechanism offered for molten BiCl3 is simply the Grotthuss mechanism for conduction, applicable not just to H+ ions, but also to halide ions in post-transition-metal halide melts. Second, it is conjectured that the conductivity maximum is due to rising activation energy in network-covalent (halide-bridging) melts (BiCl3, SnCl2, PbCl2), but possibly a falling Arrhenius prefactor (collision frequency) for molecular melts (HgBr2). Published by AIP Publishing.
引用
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页数:12
相关论文
共 63 条
[2]   ELECTRICAL CONDUCTANCE OF SALTS IN LIQUID IODINE .I. IODIDE DONOR SOLUTES [J].
BEARCROFT, DJ ;
NACHTRIEB, NH .
JOURNAL OF PHYSICAL CHEMISTRY, 1967, 71 (02) :316-+
[3]   ELECTRICAL CONDUCTANCE OF SALTS IN LIQUID IODINE .2. IODIDE ACCEPTOR SOLUTES [J].
BEARCROFT, DJ ;
NACHTRIEB, NH .
JOURNAL OF PHYSICAL CHEMISTRY, 1967, 71 (13) :4400-+
[4]   THE ELECTRIC CONDUCTIVITY AND THE ACTIVATION ENERGY OF IONIC MIGRATION OF MOLTEN SALTS AND THEIR MIXTURES [J].
BLOOM, H ;
HEYMANN, E .
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1947, 188 (1014) :392-414
[5]  
BOCKRIS J.O'M., 1970, MODERN ELECTROCHEMIS, V1, DOI 10.1007/978-1-4615-8600-5
[6]   RAMAN SPECTRA AND STRUCTURE OF MOLTEN STANNOUS CHLORIDE AND MOLTEN MIXTURES OF STANNOUS CHLORIDE AND POTASSIUM CHLORIDE [J].
CLARKE, JHR ;
SOLOMONS, C .
JOURNAL OF CHEMICAL PHYSICS, 1967, 47 (05) :1823-&
[7]   The origin of the conductivity maximum in molten salts. I. Bismuth chloride [J].
Clay, Adam T. ;
Kuntz, Colin M. ;
Johnson, Keith E. ;
East, Allan L. L. .
JOURNAL OF CHEMICAL PHYSICS, 2012, 136 (12)
[8]   PROTON CONDUCTANCE AND THE EXISTENCE OF THE H3O ION [J].
CONWAY, BE ;
BOCKRIS, JO ;
LINTON, H .
JOURNAL OF CHEMICAL PHYSICS, 1956, 24 (04) :834-850
[9]  
Corradini D, 2016, NAT CHEM, V8, P454, DOI [10.1038/nchem.2450, 10.1038/NCHEM.2450]
[10]   Ultrasoft primitive model of polyionic solutions: Structure, aggregation, and dynamics [J].
Coslovich, Daniele ;
Hansen, Jean-Pierre ;
Kahl, Gerhard .
JOURNAL OF CHEMICAL PHYSICS, 2011, 134 (24)