Lithium Pentazolate Synthesized by Laser Heating-Compressed Lithium Azide and Nitrogen
Miao Zhou, Minghong Sui, Xuhan Shi, Zitong Zhao, Linlin Guo, Bo Liu, Bo Liu, Ran Liu, Peng Wang, Bingbing Liu, Bingbing Liu
Abstract
Searching for polynitrogen compounds has attracted great attention due to their potential applications as high energy density materials. Here, we report a facile approach to the synthesis of a solid lithium pentazolate (LiN5) compound by compressing lithium azide and molecular nitrogen under high pressure with laser heating. The formation of LiN5 with the crystal structure P21/m-LiN5 was identified according to the appearance of the vibrational modes of N5– rings in Raman spectra and synchrotron X-ray diffraction measurements under high pressure. The LiN5 remains stable down to 18.5 GPa upon decompression. The bond lengths in N5– are between single- and double-bond lengths. This study indicates that the precursor can effectively tune the high-pressure phase of pentazolate, providing us an alternative route to synthesize a polynitrogen compound with a novel structure.