Novel ternary Zintl phosphide halides Ba₃P₅X (X = Cl, Br) with 1D helical phosphorus chains: synthesis, crystal and electronic structure

Abstract

Black single crystals of two novel ternary phosphide halides, Ba3P5Cl and Ba3P5Br, were grown using molten metal Pb-flux high-temperature reactions. These compounds were structurally characterized with the aid of the...

Completing the Ba–As Compositional Space: Synthesis and Characterization of Three New Binary Zintl Arsenides, Ba3As4, Ba5As4, and Ba16As11

“…The disorder of the As1 site, although less pronounced compared to that of Sb1 in Ba 16 Sb 11 , still reveals a non-negligible occupancy of the As1B site (Wyckoff 8f ), with a site occupancy factor (SOF) of 0.034 (4). Combined with the SOF of 0.468 (7) for the As1A site (Wyckoff 4d), we yield the slightly off-stoichiometric composition of Ba 16 As 11.07 (2) , similar to the situation in the isostructural Ba 16 Sb 11.2(1) [15]. For simplification, we use the simplified Ba 16 As 11 formula throughout the manuscript, although the reader should be aware that the refined composition is non-stoichiometric for both barium arsenide and antimonide.…”

“…The ability of pnictogen atoms to form homoatomic bonds noticeably diversifies the structural abundance of Zintl pnictides [3]. Examples of such can be seen in many different materials, with [P plane ] 1− square layers present in LnSiP 3 (Ln = La, Ce) [6], P − helices in Ba 3 P 5 Cl [7], and zigzag [Pn 4 ] 4− tetramers in A 5 Pn 4 (A = K, Rb, Cs and Pn = As, Sb, Bi) [8], as well as materials with multiple anionic subunit types, such as A 11 Pn 10 (A = Ca, Sr, Ba, Eu, Yb and Pn = P, As, Sb, Bi) with linear [Pn 2 ] 4− dumbbells and square [Pn 4 ] 4− units, Ca 2 As 3 = Ca 8 As 12 with [As 4 ] 6− and [As 8 ] 8− oligomers, or A 14 MPn 11 (A = Ca, Sr, Ba, Eu; M = Al, Mn, Zn, Cd; Pn = P, As, Sb, Bi) with linear [Pn 3 ] 7− trimer and [MPn 4 ] tetrahedra [9][10][11]. These structural motifs exemplify the diversity of the observed covalent substructures within Zintl pnictides and their great potential for studying structureproperty relationships.…”