Syntheses, structures, and optical properties of Ba4MInSe6 (M=Cu, Ag)

Synthesis, Structure and Bonding, Optical Properties of Ba4MTrQ6 (M=Cu, Ag; Tr=Ga, In; Q=S, Se)

“…The absorption spectrum of Ba 4 AgGaSe 6 (2) is also provided in the Supporting Information, and its optical band gap is approximately 2.50 eV, which is comparable to the values of 2.41 eV for Ba 4 AgInSe 6 and 2.23 eV for Ba 4 CuInSe 6 . [34] The band gap of 1, 2, and 4 are larger than that of AgGaS 2 (2.64 eV), AgInS 2 (1.90 eV), and AgGaSe 2 (1.8 eV). Such phenomena can be understood in terms of the concept of "dimensional reduction", which implies that structures with lower dimensionality should have larger energy band gaps.…”

“…[29,30] Furthermore, In 4 Pb x Sn y Se 3 is a promising candidate for mid-temperature thermoelectric materials with an excellent figure of merit (ZT) value of 1.4 at 733 K. [31,32] Although many mixed metal multi-chalcogenides have been reported, quaternary examples containing d 10 transition-metal ions such as Cu 1 + and Ag 1 + are rare. [33][34][35] It was reported that Cu I and Ag I ions tend to exhibit highly diversified and flexible coordination numbers with chalcogens. Hence, cuprous-and argentous-based chalcogenides are also able to display interesting structural characters.…”

“…[36,37] Ba 2 AgInS 4 features a 2D [AgInS 4 ] 4À layer built from AgS 3 triangles and InS 4 tetrahedra, [36] and Ba 4 MInSe 6 (M = Cu, Ag) contains a 1D [(M/In)Se 6 ] 8À chain based on (M/In)Se 4 tetrahedra. [34] Intrigued by their rich structural types and novel physical properties, we systematically explored the quaternary Ba-Cu/Ag-Ga/In-S/Se system. Our studies led to the discovery of a series of new quaternary chalcogenides, Ba 4 AgGaQ 6 (Q = S, Se) and Ba 4 MInS 6 (M = Cu, Ag).…”

“…For example, Ba 4 MGa 5 Q 12 (M=Cu, Ag; Q=S, Se) adopt a noncentrosymmetric 3D framework based on MQ 4 and GaQ 4 tetrahedra and strong second harmonic generation responses have been observed 36. 37 Ba 2 AgInS 4 features a 2D [AgInS 4 ] 4− layer built from AgS 3 triangles and InS 4 tetrahedra,36 and Ba 4 MInSe 6 (M=Cu, Ag) contains a 1D [(M/In)Se 6 ] 8− chain based on (M/In)Se 4 tetrahedra 34. Intrigued by their rich structural types and novel physical properties, we systematically explored the quaternary Ba‐Cu/Ag‐Ga/In‐S/Se system.…”

Five New Chalcohalides, Ba3GaS4X (X = Cl, Br), Ba3MSe4Cl (M = Ga, In), and Ba7In2Se6F8: Syntheses, Crystal Structures, and Optical Properties

“…The complete coordination environments of cations are shown in Figure 2C. The In atom is connected with four Se atoms in perfect tetrahedra geometry with In−Se interatomic distance of 2.525(1) Å, (Table 3) a little shorter than those in Ba 4 AgInSe 6 (2.612(1) to 2.660(1) Å) 33 and Ba 2 InYSe 5 (2.505(1) to 2.684(1) Å). 34 The 8-fold Ba1 atom is enjoined with six Se atoms and two Cl atoms to form bicapped trigonal prisms with two Cl atoms as caps.…”