High-pressure synthesis and structure of the new niobium phosphide Nb₂P₅

Abstract

Nb2P 5 was prepared by reaction of the elements at 3-5 GPa and 1273 K using a cubic-anvil-type apparatus.The crystal is orthorhombic, Pnma, with a = 16.742 (3), b = 3.3499 (6), c = 7.912 (1) A, Z = 4, and D x = 5.10 Mg m -a. The structure was refined to R = 0.037 for 1198 independent reflections. The structure of Nb2P 5 is closely related to the OsGe2-type structure. Zigzag P~ chains are additionally inserted along the b axis between the Os2Ge 4 rhombic prisms of the OsGe2-type structure. Nb2P s is a metallic conductor and shows Pauli paramagnetism.

The Remarkable Anisotropic Compressibility and Metallic CrCr Chains in Topological Semimetal CrP4 under High Pressure

“…[23] By counting two electrons for each of the short near-neighbor interactions, the Cr atoms obtain the oxidation number þ2. There are no other neighbors within the bonding distance; thus, sp 3 mixing is a good approximation for the P atoms in CrP 4 . The Cr─Cr atomic distance in CrP 4 under ambient conditions is 3.18 Å, which exceeds the range of Cr─Cr bonding.…”

“…Phosphorus (P), as one of the VA group elements in the periodic table, is highly reactive and can form many phosphides with metal elements such as alkaline-earth metal and transition metals. From a stoichiometric point of view, the metal phosphides can be divided into two groups ranging from metal-rich phosphides, like M 3 P (M ¼ 3d transition metals), [1] to polyphosphides, such as the reported NiP 2 , [2] Nb 2 P 5 , [3,4] CoP 3 , [5] and CrP 4 . [6] Metal (M) phosphides exhibit interesting physical and chemical properties due to their abundant crystal structure.…”

A comprehensive study of the thermophysical and optoelectronic properties of Nb2P5 via ab-initio technique

“…Among all the elements in the periodic table, phosphorus (P) is one of the most active chemically. Phosphorous can exist as a standalone anion as well as in a network of polyanions with covalent P−P bonds that can usually be found in different forms of metal phosphides with different stoichiometries ranging from metal-rich phosphides (e.g., T 3 P, where T denotes metallic element), to phosphorous-rich polyphosphides (such as TP 4 , where T = Cr, Mn, and Fe) [1][2][3]. In recent decades a large family of metal phosphides has been drawing continuous interest of physics, chemistry and materials science research community because of its earth-abundance as well as their diverse and sometimes exotic physical and chemical properties.…”

“…In 1980, Nb 2 P 5 was first synthesized by the high-pressure technique [1]. The electrical and magnetic properties were only measured down to ~77 K, which exhibits band paramagnetism and a metallic conduction behavior.…”

“…A few of the physical properties, such as structural, high pressure crystal growth, electronic band structure, and superconducting state of Nb 2 P 5 , have been studied both theoretically and experimentally so far [1,2]. Quite surprisingly, most of physical properties, e.g., elastic, electronic (DOS, charge density distribution, electron density difference), thermo-physical, Mulliken population analysis, and optical properties of this interesting metallic phosphide Nb 2 P 5 have not been explored at all.…”