A realistic three-dimensional (3D) kerogen molecular model adds significant values in petrographical evaluation in shale, especially it is essential to conduct molecular simulation for gas storage and transport behaviors in shale. In this study, the 3D kerogen molecular structure of Marcellus shale was reconstructed based on molecular simulation, and eight experimental techniques, including ¹³C nuclear magnetic resonance (¹³C NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), elemental analysis, helium porosimetry, low-pressure CO₂ adsorption, and radial distribution function (RDF) obtained from synchrotron X-ray. The XPS data provides elemental compositions and the contents of functional groups of carbon, oxygen, nitrogen and sulfur on the kerogen surface. FTIR and ¹³C NMR spectroscopy provide the contents of aliphatic chains and aromatic rings. The two-dimensional (2D) kerogen molecular structure was initially constructed, and the connection of kerogen fragments was verified by comparing the experimental and calculated ¹³C NMR spectra. Then, fourteen 2D kerogen molecules were used to reconstruct the 3D kerogen molecular structure. Experimental helium density and micropore volume were used to verify the density and micropore structure of the final 3D model. Experimental RDF data were also used to analyze the spatial distribution of the kerogen atoms. The reconstructed 3D kerogen molecular structure of Marcellus shale contains 5936 atoms (C₂₈₅₆H₂₄₉₂N₅₆O₅₃₂), and the unit cell dimension is 3.755 × 3.755 × 3.755 nm. This study provides a systematic approach to establish a realistic 3D kerogen molecular model by leveraging the advantages of various techniques. The established Marcellus kerogen model lays the foundation for future fluid transport and storage studies.

逼真的三维 (3D) 干酪根分子模型为页岩的岩相评价增加了重要价值，尤其是对页岩中的气体储运行为进行分子模拟至关重要。本研究基于分子模拟和¹³ C 核磁共振 ( ¹³ C NMR) 光谱、傅里叶变换红外光谱 (FTIR)、X 射线光电子能谱等 8 种实验技术重建了 Marcellus 页岩的 3D 干酪根分子结构。(XPS)、高分辨率透射电子显微镜 (HRTEM)、元素分析、氦气孔隙率测定、低压 CO ₂吸附和从同步加速器 X 射线获得的径向分布函数 (RDF)。XPS 数据提供了干酪根表面的元素组成和碳、氧、氮和硫官能团的含量。FTIR 和¹³ C NMR 光谱提供了脂肪链和芳香环的含量。初步构建了二维（2D）干酪根分子结构，通过对比实验和计算验证了干酪根碎片的连接性¹³C核磁共振谱。然后，使用 14 个 2D 干酪根分子重建 3D 干酪根分子结构。实验氦密度和微孔体积用于验证最终 3D 模型的密度和微孔结构。实验 RDF 数据也用于分析干酪根原子的空间分布。Marcellus 页岩重建的 3D 干酪根分子结构包含 5936 个原子 (C ₂₈₅₆ H ₂₄₉₂ N ₅₆ O ₅₃₂)，晶胞尺寸为 3.755 × 3.755 × 3.755 nm。这项研究提供了一种系统方法，可以利用各种技术的优势来建立逼真的 3D 干酪根分子模型。已建立的 Marcellus 干酪根模型为未来的流体输送和储存研究奠定了基础。