Refinement of the crystal structure of dibarium tetrasilicide, Ba2Si4

Abstract

Source of materialThree samples, Ba 2Si3.8,B a 2 Si4 and Ba2Si4.4 were prepared by arc melting of appropriate amounts of the elements (Ba, dendritic, 99.9 %Alfa Aesar; Si, pieces, 99.999 %Alfa). The reguli were sealed in Ta ampoules enclosed in evacuated quarz glass tubes. After subsequent annealing at 800°C for one week, the samples were quenched in ice water. Experimental detailsDue to sensitivity to air and humidity, the investigated singlecrystal was sealed into aglass capillary under purified argon. Lattice parameters were refined from powder diffraction data (CuKa 1 , l =1 .540562 Å), using 50 -7 0n on-overlapping reflections between 18°£ 2q £ 80°applying LaB 6 as internal standard (NIST, a =4.15692 Å).

BaSi2as a promising low-cost, earth-abundant material with large optical activity for thin-film solar cells: A hybrid density functional study

“…It can be noted that the calculated lattice parameters are in excellent agreement with reported experimental data. 20,21) Moreover, the calculated average ¤ Si-Si bond length (2.40 Å) is in good agreement with the experimental value of 2.403 Å reported by Goebel et al 21) Hence, the use of the hybrid functional enables us to successfully describe the structural properties of BaSi 2 .…”

Post-annealing effects on the surface structure and carrier lifetime of evaporated BaSi2 films

“…2, the peak positions agree with the theoretical ones calculated using the crystal structure data of BaSi 2 . 25) All diffraction peaks are therefore attributed to BaSi 2 , which indicates that the impurities detected by Raman spectroscopy are in small quantity and their location is limited around the surface. It is also found from Fig.…”

“…The X-ray incidence angle was 3.8°. The theoretical powder pattern for the orthorhombic BaSi 2 phase, which was calculated using the reported structural data, 25) is also displayed.…”

Zintl Phases K4–xNaxSi4 (1 ≤ x ≤ 2.2) and K7NaSi8: Synthesis, Crystal Structures, and Solid‐State NMR Spectroscopic Investigations

“…Binary phases include A 4 T 4 ( A = Na–Cs),, A 4 Ge 9 ( A = K–Cs) and A 12 T 17 (A = Na, K), and the ternary phases A 7 NaSi 8 ( A = Rb, Cs), A 7 NaGe 8 ( A = K–Cs),, Cs 2 Na 2 Ge 4 and K 6 Rb 6 Si 17 have also been reported. Additionally, the semiconductor Ba 2 Si 4 with slightly distorted [Si 4 ] 4– units, as well as the metallic Zintl phase Ba 3 Si 4 comprising butterfly‐like [Si 4 ] 6– anions have been prepared.…”