Carbon-encapsulated iron-cementite (Fe-Fe₃C) nanoparticles, promising nanomaterials for medicine due to their valuable magnetic properties, were synthesized by a single-step solid-state pyrolysis of iron phthalocyanine. To obtain required magnetic characteristics of such nanoparticles by governing of the pyrolysis conditions one needs reliable structural information of the atomic architecture of the obtained nanoparticles of composition (Fe-Fe₃C), in which Fe atoms have different types of the local surrounding. The latter complicates the structural characterization of samples, which was performed using the complementary methods of TEM, SAXS, XRD, XANES, and EXAFS and the results of simulations by the method of reactive force field molecular dynamics (ReaxFF MD). The size of the particles is on the order of 10 nm with cementite concentration of about 60–70 wt%. The simulations enabled to reveal that the most plausible combinations of the local structures of Fe atoms in (Fe-Fe₃C) nanoparticle result in the difference of corresponding atomic pair radial distribution functions relatively to iron (RDF), which can be further filtered through the comparison with experimentally obtained RDF for iron atoms in the studied sample. Such RDF was derived from experimental Fe K-edge EXAFS in the sample by Fourier transform multi-shell processing within harmonic approximation and using the results of the analysis of SAXS, XRD, and XANES. The used approach, based on the filtering of ReaxFF MD-calculated RDFs via comparison with the EXAFS derived RDF, revealed that for particles of composition (Fe-Fe₃C) with XRD derived iron:cementite ratio of \(\sim 40\):60 wt% and sizes bigger than 4 nm, the architecture with iron in core region of particle and cementite in its shell (Fe@Fe₃C) is the most probable for the mean nanoparticle comparing with architectures of the inverted core-shell (Fe₃C@Fe) or the mixture of iron and cementite phases (Fe+Fe₃C).

通过单步固态热解酞菁铁，合成了碳包裹的铁-钙铁矿（Fe-Fe ₃ C）纳米粒子，由于其有价值的磁性能而有望用于医学。为了通过控制热解条件获得这种纳米颗粒所需的磁性，需要获得所获得的组成（Fe-Fe _3）纳米颗粒的原子结构的可靠结构信息。C），其中Fe原子具有不同类型的局部周围环境。后者使样品的结构表征复杂化，这是通过使用TEM，SAXS，XRD，XANES和EXAFS的互补方法进行的，以及通过反作用力场分子动力学方法（ReaxFF MD）进行的模拟结果。颗粒尺寸约为10 nm，渗碳体浓度约为60-70 wt％。通过模拟可以揭示（Fe-Fe ₃C）纳米粒子导致相应的原子对径向分布函数相对于铁（RDF）有所不同，可以通过与研究所得样品中铁原子的实验获得的RDF比较来进一步过滤。这种RDF是通过谐波近似中的傅立叶变换多壳处理并使用SAXS，XRD和XANES的分析结果从样品中的实验Fe K-edge EXAFS衍生而来的。使用的方法基于ReaxFF MD计算的RDF与EXAFS衍生的RDF的比较过滤，结果表明，对于成分（Fe-Fe ₃ C）的颗粒，XRD衍生的铁：钙铁矿比率为\（\ sim 40 \）相较于倒置的核-壳结构（：@ 60 wt％，尺寸大于4 nm，颗粒核心区域具有铁，壳中具有渗碳体（Fe @ Fe ₃ C）的结构最有可能成为平均纳米颗粒（ Fe ₃ C @ Fe）或铁和渗碳体相的混合物（Fe + Fe ₃ C）。