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LiGa is Zintl Phase structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional and consists of two LiGa frameworks. Li is bonded to four equivalent Ga atoms to form distorted corner-sharing LiGa4 tetrahedra. All Li–Ga bond lengths are 2.71 Å. Ga is bonded to four equivalent Li atoms to form distorted corner-sharing GaLi4 tetrahedra.
LiGa(SeO3)2 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.01 Å) and two longer (2.03 Å) Li–O bond lengths. Ga3+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Ga–O bond distances ranging from 1.99–2.03 Å. Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.72–1.75 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ga3+, and one Se4+ atom. In the second O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Ga3+, and one Se4+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Ga3+ and one Se4+ atom.
LiGa(PO3)4 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with four equivalent PO4 tetrahedra and an edgeedge with one GaO6 octahedra. There are two shorter (1.93 Å) and two longer (2.08 Å) Li–O bond lengths. Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one LiO4 tetrahedra. There is four shorter (1.97 Å) and two longer (2.00 Å) Ga–O bond length. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one GaO6 octahedra, corners with two equivalent LiO4 tetrahedra, and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of P–O bond distances ranging from 1.47–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent GaO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–49°. There are a spread of P–O bond distances ranging from 1.51–1.60 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ga3+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Li1+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ga3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Ga3+, and one P5+ atom.
LiGaSi2O6 is Esseneite structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.54 Å. Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with two equivalent GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.92–2.15 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent GaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–60°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Li1+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Ga3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Ga3+, and one Si4+ atom.
LiGaSi2O6 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.39 Å. Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.92–2.15 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent GaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–59°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent GaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–60°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+, one Ga3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Ga3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Ga3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Ga3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and two equivalent Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Si4+ atoms.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
LiGaGe2Se6 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Li1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Li–Se bond distances ranging from 2.69–2.90 Å. Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with four GeSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.44–2.46 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four Se2- atoms to form GeSe4 tetrahedra that share corners with two equivalent GaSe4 tetrahedra and corners with two equivalent GeSe4 tetrahedra. There are a spread of Ge–Se bond distances ranging from 2.38–2.44 Å. In the second Ge4+ site, Ge4+ is bonded to four Se2- atoms to form GeSe4 tetrahedra that share corners with two equivalent GaSe4 tetrahedra and corners with two equivalent GeSe4 tetrahedra. There are a spread of Ge–Se bond distances ranging from 2.39–2.44 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to one Li1+ and two Ge4+ atoms. In the second Se2- site, Se2- is bonded in a water-like geometry to two Ge4+ atoms. In the third Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Ga3+, and one Ge4+ atom. In the fourth Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+, one Ga3+, and one Ge4+ atom. In the fifth Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+, one Ga3+, and one Ge4+ atom. In the sixth Se2- site, Se2- is bonded in a water-like geometry to one Ga3+ and one Ge4+ atom.
Abstract Most ternary sulfides belonging to the MGaS 2 structure‐type have been known for many years and are well‐characterized. Surprisingly, there have been no reports of the NaGaS 2 composition, which contains Na, a monovalent cation slightly larger in size than Li, found in LiGaS 2 , a compound known for its non‐linear optical properties. Now it is demonstrated for the first time that the unique reversible water absorption in NaGaS 2 has resulted in its absence from previous reports owing to difficulties encountered when characterizing this compound by SC XRD. The layered structure of this compound coupled with uniquely easy migration of water molecules between the layers allows for ion exchange with 3d and 5f metal cations. Some cations, for example, Ni 2+ , facilitate exfoliation of the layers, providing a facile synthetic route to a new class of 2D chalcogenide materials and furthermore demonstrating that NaGaS 2 can readily uptake uranyl species from aqueous solutions.
Most ternary sulfides belonging to the MGaS 2 structure-type have been known for many years and are well-characterized. Surprisingly, there have been no reports of the NaGaS 2 composition, which contains Na, a monovalent cation slightly larger in size than Li, found in LiGaS 2 , a compound known for its non-linear optical properties. Herein we demonstrate for the first time that the unique reversible water absorption in NaGaS 2 has resulted in its absence from the literature due to the difficulties that one encounters when characterizing this compound by SC XRD. The layered structure of this compound coupled with uniquely easy migration of water molecules between the layers allows for ion exchange with 3d and 5f metal cations. We established that some cations, e.g. Ni 2+ , facilitate exfoliation of the layers, providing a facile synthetic route to a new class of 2D chalcogenide materials and, in addition, demonstrating that NaGaS 2 can readily uptake uranyl species from aqueous solutions.
The integration of lithium based compounds (e.g., Li:NiO/Ga 2 O 3 , LiGa 5 O 8 /Ga 2 O 3 ) in Ga 2 O 3 based pn-heterojunctions raises concerns about interface stability, i.e., Li diffusion effects on Ga 2 O 3 properties. In this work the ex-situ diffusion of Li is investigated in three different Ga 2 O 3 epilayers systems [(001) κ-Ga 2 O 3 and (−201) β-Ga2O3 heteroepitaxy on (001) α-Al 2 O 3 , and (010) β-Ga 2 O 3 homoepitaxy] at relevant temperatures for the synthesis / processing of Li-based epilayers. It is here experimentally demonstrated and quantified the Li diffusion in all the investigated Ga 2 O 3 epilayers systems and Li bulk (D Li,bulk ) and 2D defects (D Li,2D ) diffusion coefficients are provided. In the case of the (010) β-Ga 2 O 3 homoepitaxial layer (nominally free of structural defects), hybrid functional theory calculations foresee a diffusion mechanism mediated by Ga vacancies (VGa). Moreover, in the (010) β-Ga 2 O 3 homo-layer a significant effect on its functional properties (e.g., additional Raman vibrational modes, induced conductivity in an otherwise insulating sample) upon the Li-diffusion process is experimentally highlighted and tentatively related to the passivation of acceptor defects (i.e., formation of V Ga -nLi complexes).
Lithium alloying reactions are beneficial in promoting uniform plating and stripping of lithium metal in all-solid-state batteries. First-principles calculations are performed to predict thermodynamic, kinetic, and mechanical properties of lithium and several important Li–M alloys (M = Mg, Ag, Zn, Al, Ga, In, Sn, Sb, and Bi). While the Li–Mg binary system forms a solid solution, most other lithium–metal alloys prefer stoichiometric intermetallic compounds with common local motifs that enable fast Li diffusion. Lithium and Li-rich alloys exhibit an unusually flat energy landscape along paths that connect BCC to close-packed structures like FCC and HCP, with important implications for mechanical properties. Very low migration barriers for Li diffusion that rival those of superion conductors are predicted, both in pure Li and in Li–M intermetallics. However, vacancy concentration, which is crucial for substitutional diffusion, is predicted to be low in metallic Li and most Li–M intermetallics. Compounds such as B32 LiAl and LiGa as well as D0 3 Li 3 Sb and Li 3 Bi exhibit structural vacancies at higher ends of their voltage windows, which together with low migration barriers leads to exceptionally high Li mobilities. In the Li–Mg solid solution, the addition of Mg is found to decrease the vacancy tracer diffusion coefficient by an order of magnitude.
An aspect of the present disclosure is a microbial cell that includes a genetic modification resulting in the expression of a deficient form of an endogenous dioxygenase, and a gene encoding an exogenous dioxygenase and a promoter sequence, where the endogenous dioxygenase includes PcaH and PcaG, the exogenous dioxygenase includes LigA and LigB, the microbial cell is capable of growth utilizing at least one of a cellulose decomposition molecule or a lignin decomposition molecule, and the microbial cell is capable of producing 2-hydroxy-2H-pyran-4,6-dicarboxylic acid.