Preparation and Structure of the Ion-Conducting Mixed Molecular Glass Ga₂I_3.17

Abstract

Modern functional glasses have been prepared from a wide range of precursors, combining the benefits of their isotropic disordered structures with the innate functional behavior of their atomic or molecular building blocks. The enhanced ionic conductivity of glasses compared to their crystalline counterparts has attracted considerable interest for their use in solid-state batteries. In this study, we have prepared the mixed molecular glass Ga 2 I 3.17 and investigated the correlations between the local structure, thermal properties, and ionic conductivity. The novel glass displays a glass transition at 60 °C, and its molecular make-up consists of GaI 4 – tetrahedra, Ga 2 I 6 2– heteroethane ions, and Ga + cations. Neutron diffraction was employed to characterize the local structure and coordination geometries within the glass. Raman spectroscopy revealed a strongly localized nonmolecular mode in glassy Ga 2 I 3.17 , coinciding with the observation of two relaxation mechanisms below T g in the AC admittance spectra.

Synthesis of Ternary and Quaternary Group III-Arsenide Colloidal Quantum Dots via High-Temperature Cation Exchange in Molten Salts: The Importance of Molten Salt Speciation

“…We compare these to the directly synthesized KGaBr 4– x I x ( x = 0–4) salts (violet to green traces). The two parent compounds, KGaBr 4 and KGaI 4 show a single strong peak at ∼210 and ∼145 cm –1 which correspond well with symmetric Ga-X stretch modes ( v 1 ) for X = Br and X = I respectively . For the mixed halide KGaX 4 salts, we observe several additional Raman peaks appear.…”

“…Temperature-dependent Raman spectra show that three distinct peaks corresponding to the v 1 , v 4 and v 2 at 143, 75, and 50 cm –1 remain. We observe a small peak at ∼115 cm –1 which may correspond to small amounts of the [Ga 2 I 6 ] 2– ion which could form if a small amount of metallic gallium impurities were present in the system . Importantly we do not see any peaks or shoulders which correspond to Lewis acidic species such as GaI 3 or the [Ga 2 I 7 ] − ion.…”

“…We observe a small peak at ∼115 cm −1 which may correspond to small amounts of the [Ga 2 I 6 ] 2− ion which could form if a small amount of metallic gallium impurities were present in the system. 40 Importantly we do not see any peaks or shoulders which correspond to Lewis acidic species such as GaI 3 or the [Ga 2 I 7 ] − ion. Directly overlaying the Raman spectra for KGaI 4 and KGaI 4 in contact with excess AI (A = Li,K) shows no discernible difference (Figure S12) indicating 2KGaI 4 → KI +KGa 2 I 7 does not happen to an appreciable amount.…”

“…The two parent compounds, KGaBr 4 and KGaI 4 show a single strong peak at ∼210 and ∼145 cm −1 which correspond well with symmetric Ga-X stretch modes (v 1 ) for X = Br and X = I respectively. 30 For the mixed halide KGaX 4 salts, we observe several additional Raman peaks appear. Two of the peaks match with parent KGaBr 4 and KGaI 4 respectively.…”

Local Order in Liquid Gallium–Indium Alloys

“…Only the time-of-flight data below a neutron energy of 0.33 eV were used to avoid the strong neutron resonance of indium. 73 Further details on data collection and correction can be found in ref ( 74 ). For the EPSR analysis of liquid Ga and Ga 0.858 In 0.142 , simulation boxes containing 1000 Ga atoms, and 1716 Ga plus 284 In atoms, respectively, were constructed according to experimental densities.…”