Steele Brad A, Oleynik Ivan I
Department of Physics, University of South Florida , 4202 East Fowler Avenue, Tampa, Florida 33620, United States.
J Phys Chem A. 2017 Mar 2;121(8):1808-1813. doi: 10.1021/acs.jpca.6b12900. Epub 2017 Feb 16.
Two new crystalline compounds, pentazole (NH) and ammonium pentazolate (NH)(N), both featuring cyclo-N are discovered using a first-principles evolutionary search of the nitrogen-rich portion of the hydro-nitrogen binary phase diagram (NH, x ≥ y) at high pressures. Both crystals consist of the pentazolate N anion and ammonium NH or hydrogen H cations. These two crystals are predicted to be thermodynamically stable at pressures above 30 GPa for (NH)(N) and 50 GPa for pentazole NH. The chemical transformation of ammonium azide (NH)(N) mixed with dinitrogen (N) to ammonium pentazolate (NH)(N) is predicted to become energetically favorable above 12.5 GPa. To assist in identification of newly synthesized compounds in future experiments, the Raman spectra of both crystals are calculated and mode assignments are made as a function of pressure up to 75 GPa.
通过对高压下氢 - 氮二元相图富氮部分（NH，x≥y）进行第一性原理进化搜索，发现了两种新的晶体化合物：五唑（NH）和五唑酸铵（NH）（N），二者均具有环 - N结构。两种晶体均由五唑酸根N阴离子和铵根NH或氢离子H阳离子组成。预计这两种晶体在压力高于30 GPa时对于五唑酸铵（NH）（N）以及在压力高于50 GPa时对于五唑NH是热力学稳定的。预计叠氮化铵（NH）（N）与氮气（N）混合转化为五唑酸铵（NH）（N）的化学转变在压力高于12.5 GPa时在能量上变得有利。为了协助在未来实验中鉴定新合成的化合物，计算了两种晶体的拉曼光谱，并给出了高达75 GPa压力下的模式归属。
