Recrystallization of CL-20 and HNFX from Solution for Rigorous Control of the Polymorph Type: Part I, Mathematical Modeling using Molecular Dynamics Method
Recrystallization of CL-20 and HNFX from Solution for Rigorous Control of the Polymorph Type: Part I, Mathematical Modeling using Molecular Dynamics Method
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DOI：
10.1080/07370650600672082
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发表时间：
2006-07
影响因子：
2.1
通讯作者：
Z. Peralta-Inga;N. Deǧirmenbaşı;U. Olgun;H. Gocmez;D. Kalyon
中科院分区：
文献类型：
--
作者：
Z. Peralta-Inga;N. Deǧirmenbaşı;U. Olgun;H. Gocmez;D. Kalyon
采用组合计算方法研究了CL-20和HNFX形成不同晶型的重结晶过程（在基于分子动力学的计算中，在存在和不存在溶剂分子的情况下进行多晶型预测）和实验分析，包括无数条件下的微结晶、新型结晶方法、使用X射线粉末衍射分析多晶型物和Rietveld分析，采用DSC、TGA、偏光显微镜和SEM等常规方法对样品进行了表征（实验结果见本文第二部分）。在调查中，所有三组溶剂：极性质子，非极性非质子和偶极非质子溶剂。我们的计算表明（与早期的研究一致），CL-20和HNFX具有不同密度的多晶型物是可能的。然而，如本文的第二部分所示，尽管实验揭示了CL-20在不同重结晶条件下的不同多晶型物类型，α、β、γ、α，但我们对HNFX的所有实验工作都产生了与CiR-3有关的晶体，CiR-3是HNFX唯一已知的多晶型物。
The recrystallization of CL-20 and HNFX to form different polymorphs was investigated by employing combinations of computations (polymorph predictions with and without the presence of the solvent molecules in the molecular dynamics based calculations) and experimental analyses, including micro-crystallization under a myriad of conditions, novel means of crystallization, analysis of polymorphs using X-ray powder diffraction, and Rietveld analysis, and the use of conventional methods including DSC, TGA, polarized microscopy and SEM (with the experimental results reported in Part II of this paper). In the investigation all three groups of solvents: polar protic, non-polar aprotic, and dipolar aprotic solvents were employed. Our computations have revealed (in agreement with earlier studies) that polymorphs with various densities for both CL-20 and HNFX are possible. However, as part II of this paper will show although the experiments revealed different polymorph types, α, β, γ, ϵ for CL-20 under different recrystallization conditions all of our experimental work for HNFX have resulted in crystals pertaining to Ci R-3, which is the only known polymorph of HNFX.