First-principles calculations of sulphur isotope fractionation in MX2 minerals, with M= Fe, Co, Ni and X2= AsS, SbS

Abstract

Iron, Co and Ni are first row transition metals and are all able to combine with S, As, and Sb to form disulphides, sulpharsenides and sulphantimonides, respectively, all of which exhibit substitutions of metal and metalloid elements in their structures. As an important tracer in the geochemistry of ore deposits, S isotope fractionation in sulphides can be used to analyse the ore-forming process and the source of ore-forming elements. However, there have been few studies of S isotope fractionation in sulpharsenides and sulphantimonides. Studying the isotope fractionation of the various members of this structural group can provide systematic information regarding S isotope fractionation in transition metal disulphides, sulpharsenides and sulphantimonides. In this paper, the S isotope fractionation parameters for Fe, Co and Ni sulpharsenides and sulphantimonides were calculated using first-principles methods based on density functional theory in the temperature range of 0-1000 ºC. Our calculations show that the order of heavy S isotope enrichment is arsenopyrite > cobaltite > gudmundite > costibite >

Bimetallic‐Based Electrocatalysts for Oxygen Evolution Reaction

“…[50] For instance, the sulfur host in metal sulfides leads to the occurrence of MS covalent bonds and MM metallic bonds as compared to that of metallic oxides due to the atomic electronegativity difference between sulfur and oxygen atoms. [51] Generally, metal oxides possess high catalytic activity and easy preparation conditions, while metal sulfides, phosphides, etc., exhibit good conductivity and their preparation is relatively difficult. Furthermore, according to the molar ratio of metal and non-metallic compositions (X = O, S, P, N, C, etc.…”

Iron and sulfur isotope factors for pyrite from experimental gamma-resonant studies and heat capacity

“…10 6 /Т 2 (K -2 ) 1 0 6 /Т 2 (K -2 ) 34 (Liu et al, 2016) Расчет из первых принципов (Blanchard et al, 2009) Мессбуэровская спектроскопия + теплоемкость (Polyakov, Mineev, 2000) Пирит-галенит эксперимент (Smith et al, 1977) Пирит-сфалерит эксперимент (Smith et al, 1977) П и р и т -г а л е н и т П и р и т-сф ал ер и т Рис. 6.…”

Safe, accurate, and precise sulfur isotope analyses of arsenides, sulfarsenides, and arsenic and mercury sulfides by conversion to barium sulfate before EA/IRMS

“…In some peculiar magmatic-hydrothermal and hydrothermal mineral deposits, the mineralogy may be dominated by arsenides, sulfarsenides, and arsenic (As) and mercury (Hg) sulfides. Arsenic is bonded to sulfur in realgar (> 90% arsenic disulfide, As 2 S 2 ), orpiment (arsenic trisulfide, As 2 S 3 ), intermediate As-S compounds (As 1−x S x ), sulfarsenides with the pyrite-structure (MAs x S 2−x , with M representing a metal such Fe, Co, Ni, Cu, Pb, Zn, Au, Ag, and platinum group elements, and x < 1), and also sulfur-containing arsenides [ 7 ]. The most common sulfarsenides in hydrothermal systems are arsenopyrite (ferrous arsenic sulfide, FeAsS) and arsenian pyrite (FeAs x S 2−x with x < 1), together with cobaltite (CoAsS), enargite (Cu 3 AsS 4 ), gersdorffite (NiAsS), and glaucodot ((Co,Fe)AsS) [ 7 , 8 ].…”

“…Arsenic is bonded to sulfur in realgar (> 90% arsenic disulfide, As 2 S 2 ), orpiment (arsenic trisulfide, As 2 S 3 ), intermediate As-S compounds (As 1−x S x ), sulfarsenides with the pyrite-structure (MAs x S 2−x , with M representing a metal such Fe, Co, Ni, Cu, Pb, Zn, Au, Ag, and platinum group elements, and x < 1), and also sulfur-containing arsenides [ 7 ]. The most common sulfarsenides in hydrothermal systems are arsenopyrite (ferrous arsenic sulfide, FeAsS) and arsenian pyrite (FeAs x S 2−x with x < 1), together with cobaltite (CoAsS), enargite (Cu 3 AsS 4 ), gersdorffite (NiAsS), and glaucodot ((Co,Fe)AsS) [ 7 , 8 ]. These sulfarsenides are often found together with cobalt–nickel mono-, di-, and tri-arsenides, which may contain up to 3 wt.% sulfur [ 9 , 10 ].…”