TY - JOUR

T1 - Gallium Trichloride Fluid: Dimer Dissociation Mechanism, Local Structure, and Atomic Dynamics

AU - Khomenko, Maxim

AU - Sokolov, Anton

AU - Tverjanovich, Andrey

AU - Bokova, Maria

AU - Kassem, Mohammad

AU - Usuki, Takeshi

AU - Bychkov, Eugene

PY - 2024/3/19

Y1 - 2024/3/19

N2 - Molten gallium trichloride emerges as a promising solvent for oxidative metal recycling. The use of supercritical fluid enhances the performance and kinetics of metal dissolution due to significantly lower viscosity in the reaction media. Additionally, the dual molecular nature of gallium trichloride, existing as edge-sharing ES-Ga 2Cl 6 dimers at low temperatures and high pressure, or flat trigonal GaCl 3 monomers in the vicinity of the critical point and low pressures, creates the possibility to tailor the chemical geometry to a particular metallic species. Nevertheless, the mechanism of dimer dissociation, local structure, and atomic dynamics in supercritical gallium trichloride fluids are not known. Using first-principles molecular dynamics, validated by comparison with our high-energy X-ray diffraction results, we illustrate the elementary steps in dimer dissociation. These include the formation of intermediate corner-sharing CS-Ga 2Cl 6 dimers, the partial disproportionation of GaCl 3 monomers at high temperatures and low pressures, changes in the local environment of molecular entities, and unusual atomic dynamics in supercritical fluids.

AB - Molten gallium trichloride emerges as a promising solvent for oxidative metal recycling. The use of supercritical fluid enhances the performance and kinetics of metal dissolution due to significantly lower viscosity in the reaction media. Additionally, the dual molecular nature of gallium trichloride, existing as edge-sharing ES-Ga 2Cl 6 dimers at low temperatures and high pressure, or flat trigonal GaCl 3 monomers in the vicinity of the critical point and low pressures, creates the possibility to tailor the chemical geometry to a particular metallic species. Nevertheless, the mechanism of dimer dissociation, local structure, and atomic dynamics in supercritical gallium trichloride fluids are not known. Using first-principles molecular dynamics, validated by comparison with our high-energy X-ray diffraction results, we illustrate the elementary steps in dimer dissociation. These include the formation of intermediate corner-sharing CS-Ga 2Cl 6 dimers, the partial disproportionation of GaCl 3 monomers at high temperatures and low pressures, changes in the local environment of molecular entities, and unusual atomic dynamics in supercritical fluids.

KW - dimer dissociation mechanism

KW - first-principles molecular dynamics

KW - supercritical gallium trichloride

UR - https://www.mendeley.com/catalogue/fa87b284-eabe-353e-b759-f3b029f8eba4/

U2 - 10.3390/molecules29061358

DO - 10.3390/molecules29061358

M3 - Article

C2 - 38542994

VL - 29

JO - Molecules

JF - Molecules

SN - 1420-3049

IS - 6

M1 - 1358

ER -