二硝酰胺胍(GDN)的晶体结构和热行为（英）

利用二硝酰胺铵(ADN)和盐酸胍在水溶液中合成了二硝酰胺胍((NH2)2C NH2] N(NO2)2-,GDN),首次培养出了用于X射线衍射的无色透明单晶。GDN属三斜晶系,空间群为P-1,晶体结构参数为:a=0.8332(5)nm,b=0.9306(6)nm,c=0.9878(6)nm,α=84.659(11)°,β=69.213(12)°,γ=67.451(12)°,V=0.6605(7)nm3,Z=4,μ=0.159 mm-1,F(000)=344,Dcalc=1.671 g.cm-3。通过DSC和TG/DTG法研究了GDN的热行为,其中第三阶段为强烈的放热分解过程,分解反应的表观活化能和指前因子分别为118.75 kJ.mol-1和1010.86s-1。GDN热爆炸的临界温度为164.09℃。GDN比ADN有更好的热稳定性。

Crystal Structure and Thermal Behavior of GDN

Guanidine dinitramide ( (NH2)2CNH2 ]+N(NO2)2-, GDN) was prepared by mixing ammonium dinitramide (ADN) and guanidine hydrochloride in water, and its structure was firstly determined by single-crystal X-ray diffraction. The crystal is triclinic, space group P-1 with crystal parameters of a=0.8332(5) nm, b=0.9306(6) nm, c=0.9878(6) nm, α=84.659(11)°, β=69.213(12)°, γ=67.451(12)°, V=0.6605(7) nm3, Z=4, μ＝0.159 mm-1, F(000)=344, and Dcalc=1.671 g·cm-3. The thermal behavior of GDN was studied with DSC and TG/DTG methods, and its thermal decomposition process can be divided into four stages, and the third stage is an intense exothermic decomposition process. The apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are 118.75 kJ·mol-1 and 1010.86 s-1, respectively. The critical temperature of thermal explosion is 164.09 ℃. GDN presents higher thermal stability than ammonium dinitramide (ADN).