Solvent effects on the geometry, electronic structure, and bonding style of Zn(N₅)₂: A theoretical study

Abstract

Nitrogen‐rich compounds involving the cyclo‐pentazole anion (cyclo‐N5−) have attracted extensive attention due to higher energy release and environmental friendliness than traditional high energy density materials (HEDMs). However, the synthesis of stable HEDMs with cyclo‐N5− is still a challenge. In this study, the effect of nine solvents on the geometrical and electronic structures and solvation energies of Zn(N5)2, one of the recently synthesized nitrogen‐rich compounds, was studied using the density functional theory and the polarized continuum model. The results indicated an increase in the stability of Zn(N5)2 in the solution phase compared to the vacuum phase, and the stability of Zn(N5)2 increases with increasing dielectric constants. The energy gap of frontier molecular orbitals and the absolute value of total energy in water are the largest, revealing that Zn(N5)2 is more stable in water than in other solvents. To understand the stabilization mechanism of Zn(N5)2 by water, further studies were performed with the natural bond orbital (NBO) analysis and the quantum theory of atoms in molecules (QTAIM) analysis using the explicit solvent model. The charge transfer and the hydrogen bonds are observed between Zn(N5)2 and water, which are beneficial to improvement of the stability of Zn(N5)2. This may indicate the solvents that have strong interactions with the cyclo‐N5− candidate may improve the possibility of success of synthesis.

Moderate Pressure Stabilized Pentazolate Cyclo-N5– Anion in Zn(N5)2 Salt

“…69 After simulating with the empirical Kamlet−Jacobs equations, the detonation velocity and detonation pressure of P1-Zn(N 5 ) 2 phase were estimated up to 12 km/s and 75 GPa, which is closely 2 and 4 times as much as that of TNT. Through comparing the detonation behavior of the salt containing cyclo-N 5 ions in AN 5 (A = H, K, Ru) 70−72 and M(N 5 ) 2 (M = Mg, Zn, Ba, Be), 73,74 the advantages of using metal cations doping are helpful to increase energy density and explosive heat.…”

New High Pressure Phases of the Zn–N System

“…Rajeswarapalanichamy et al reported that ZnN with the space group F 4̅3 m is the lowest energy phase at ambient pressure . Zn 3 N 2 is a direct bandgap n-type semiconductor structure, which has been studied recently as a promising material with great potential for photonic and electronic applications. − Binary metal azide Zn­(N 3 ) 2 is a preferred precursor for the synthesis of nitridophosphates and binary nitrides. − Recently, Ding et al reported a new Zn­(N 5 ) 2 in the solution phase involving the cyclo-pentazole anion with a stabilization mechanism considered by the charge transfer and the hydrogen bonds between Zn­(N 5 ) 2 and water . Until now, the investigations of zinc nitride compounds were limited to these four stoichiometries; no other Zn–N chemical stoichiometries were reported.…”

“…30−32 Recently, Ding et al reported a new Zn(N 5 ) 2 in the solution phase involving the cyclo-pentazole anion with a stabilization mechanism considered by the charge transfer and the hydrogen bonds between Zn(N 5 ) 2 and water. 33 Until now, the investigations of zinc nitride compounds were limited to these four stoichiometries; no other Zn−N chemical stoichiometries were reported. The high pressure phase diagrams of zinc nitride compounds as well as their novel physical or chemical properties are still unclear.…”

High-Pressure Synthesis and Stability Enhancement of Lithium Pentazolate

“…Cyclo -N 5 – has been predicted to be stabilized by coordinating with various metallic elements (Li, ,, Na, K, Rb, Cs, Be, Mg, , Ca, Sr, Ba, Al, , Ga 7 , Sc 7 , Y 7 , Cu, Zn), among which LiN 5 possesses the highest cyclo -N 5 – content (weight ratio ∼91%). Seven crystal structures ( P 2 1 -LiN 5 , P 2 1 / m -LiN 5 , P 2 1 / c -LiN 5 , C 2/ c -LiN 5 , P 6 1 22-LiN 5 , P 2 1 2 1 2 1 -LiN 5 , Pnan -LiN 5 ) have been discovered theoretically with different mass densities and energy densities under different pressure conditions, ,, but only one predicted structure ( P 2 1 / m -LiN 5 ) has been synthesized .…”