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A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

Chiral perovskites possess a huge applicative potential in several areas of optoelectronics and spintronics. The development of novel lead‐free perovskites with tunable properties is a key topic of current research. Herein, we report a novel lead‐free chiral perovskite, namely (R/S−)ClMBA2SnI4 (ClMBA=1‐(4‐chlorophenyl)ethanamine) and the corresponding racemic system. ClMBA2SnI4 samples exhibit a low band gap (2.12 eV) together with broad emission extending in the red region of the spectrum (∼1.7 eV). Chirality transfer from the organic ligand induces chiroptical activity in the 465–530 nm range. Density functional theory calculations show a Rashba type band splitting for the chiral samples and no band splitting for the racemic isomer. Self‐trapped exciton formation is at the origin of the large Stokes shift in the emission. Careful correlation with analogous lead and lead‐free 2D chiral perovskites confirms the role of the symmetry‐breaking distortions in the inorganic layers associated with the ligands as the source of the observed chiroptical properties providing also preliminary structure‐property correlation in 2D chiral perovskites. [ABSTRACT FROM AUTHOR]

We report here the preparation and characterization of two families of RP 2D perovskites including linear monoammonium cations, namely (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 with n = 4, 6, 8, 10, 12, 14 and 16. Their structural and optical properties show some similarities with, however, distinct features related to the presence of phase transitions occurring when different ligands are present. The optical properties confirm a general blue-shift for the (CnH2n+1NH3)2PbBr4 system with respect to the (CnH2n+1NH3)2PbI4 family with the PL data showing two distinct variation paths due to their excitonic emission behavior, one directly related to the chain length and another one depending on the ammonium coordination to the halogen atoms. The water stability of (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 has been assessed and the results show an improved hydrophobicity upon increasing the number of carbon atoms of the alkyl chain as well as by moving from iodide to bromide perovskites. [ABSTRACT FROM AUTHOR]

Chemical reactivity between As and N2, leading to the synthesis of crystalline arsenic nitride, is here reported under high pressure and high temperature conditions generated by laser heating in a diamond anvil cell. Single‐crystal synchrotron X‐ray diffraction at different pressures between 30 and 40 GPa provides evidence for the synthesis of a covalent compound of AsN stoichiometry, crystallizing in a cubic P213 space group, in which each of the two elements is single‐bonded to three atoms of the other and hosts an electron lone pair, in a tetrahedral anisotropic coordination. The identification of characteristic structural motifs highlights the key role played by the directional repulsive interactions between non‐bonding electron lone pairs in the formation of the AsN structure. Additional data indicate the existence of AsN at room temperature from 9.8 up to 50 GPa. Implications concern fundamental aspects of pnictogens chemistry and the synthesis of innovative advanced materials. [ABSTRACT FROM AUTHOR]

The role of halide substitution in a lead-free 2D hybrid perovskite is investigated on the BZA2SnX4 (BZA = benzylammonium; X = Cl, Br and I) system, by reporting the synthesis and the structural analysis by means of single-crystal X-ray diffraction data of the two novel compositions BZA2SnBr4 and BZA2SnCl4. In addition, the mixed composition BZA2Sn(BrxI1−x)4 (0 ≤ x ≤ 1) has been prepared by mechanochemical synthesis confirming the existence of a wide solid solubility between the two end-members. The absorption and emission spectra revealed a wide tuning of the band-gap by changing the halide, covering more than 300 nm in the visible range. Combined experimental and DFT calculations provide a complete picture of the electronic and structural properties of the BZA2SnX4 system, revealing a strong influence of the halide on the orientation for the benzylammonium cation, on the hydrogen bonding system within the perovskite network, and on the distortion of the octahedra. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]