Determination of the lattice parameters a and c for the hexagonal graphite unit cell using X-ray diffraction data.

To study the microstructural evolution of graphite and its allotropes under milling, graphite powder was processed using horizontal stainless-steel ball mills. A Ball-to-Powder Volume Ratio (BPVR) of 90 was maintained. Milling durations of 8, 16, 32, and 64 hours were investigated. This database contains the results of X-ray diffraction (XRD) analysis and includes the necessary calculations for determining the lattice parameters a and c. Measurements were performed using an Inel EQUINOX 2000 X-ray diffractometer configured with: A curved position-sensitive detector, CoKα₁ radiation (λ = 1.78901 Å), and a germanium monochromator. The acquired data were post-processed to convert results to CuKα₁ radiation (λ = 1.5406 Å) for consistency with standard references. 2θ peak positions were calibrated using a high-purity graphite standard (99.99%, Aldrich). Thanks to this analysis, it was possible to detect changes in the intensity of the main peak, shifts in the 2θ peaks, and their broadening. From these results, the variation in the lattice parameters "a" and "c" was calculated, which proved crucial for understanding the microstructural changes caused by lattice expansión. In the document titled "Determination of Lattice Parameters a and c," the calculations performed to determine the values of the unit cell parameters a and c are detailed. First, the interplanar distance was determined using Bragg's law, based on the 2θ peak positions corresponding to the (002) and (110) planes. Subsequently, using the formula for interplanar spacing in the hexagonal crystal system, the values of c and a were derived by applying the respective Miller indices (hkl) of the aforementioned planes. Additionally, this dataset comprises raw laser diffraction particle size analysis results. For the analysis, samples were dispersed in a 0.2% sodium hexametaphosphate solution (pH 10) and subjected to 5 minutes of ultrasonic bath treatment to ensure complete particle deagglomeration. The data reveal the dominant stages of graphite exfoliation and fracture, as well as the formation of micrometric aggregates after 64 hours.为研究石墨及其同素异形体在球磨过程中的微观结构演变，本研究采用卧式不锈钢球磨机对石墨粉体进行处理，并保持球料体积比（Ball-to-Powder Volume Ratio, BPVR）为90。实验考察了8、16、32及64小时的球磨时长。 本数据集包含X射线衍射（X-ray diffraction, XRD）分析结果，以及用于测定晶格参数a和c的必要计算过程。测试采用Inel EQUINOX 2000型X射线衍射仪完成，其配置包括：弧形位置敏感探测器、CoKα₁辐射（波长λ=1.78901 Å）及锗单色器。为与标准参考数据保持一致，所获原始数据经后处理转换为CuKα₁辐射（λ=1.5406 Å）下的结果。测试中以高纯度石墨标准品（纯度99.99%，Aldrich）对2θ峰位进行校准。通过本次分析，可检测到主峰强度变化、2θ峰位偏移及其峰宽展宽现象。基于上述结果，计算得到晶格参数a与c的变化量，这对理解由晶格膨胀引发的微观结构改变具有关键意义。在题为《晶格参数a与c的测定》的文档中，详细记述了用于确定晶胞参数a和c数值的计算过程：首先基于对应(002)与(110)晶面的2θ峰位，利用布拉格定律计算晶面间距；随后结合六方晶系的晶面间距公式，通过上述晶面对应的米勒指数（hkl）推导得到c与a的数值。 此外，本数据集还包含原始激光衍射粒度分析结果。粒度分析前，将样品分散于0.2%的六偏磷酸钠溶液（pH=10）中，并经5分钟超声浴处理以确保颗粒完全解聚。分析数据揭示了石墨剥离与断裂的主要阶段，以及球磨64小时后微米级团聚体的形成过程。