应用化学2025，Vol.42Issue(11)：1550-1558,9.DOI:10.19894/j.issn.1000-0518.250289
科教融合科研训练实验设计:晶体场理论下的钇铁石榴石热致变色
Integrating Science and Education in a Scientific Research Training Experiment:Thermochromism of Yttrium Iron Garnet under the Framework of Crystal Field Theory
摘要
Abstract
Crystal field theory serves as an important foundation for understanding and investigating the rich physicochemical properties of transition metal compounds.Its teaching content often focuses on the explanation of coordination structures and atomic orbitals,which tends to be highly abstract.Here,a scientific research training experimental integrating science and education is proposed,it combines the heat induced lattice changes and intuitive visual impact,guiding students to analyze the crystal field from the thermochromic phenomenon of inorganic materials,deepening their understanding of the theoretical essence and promoting the construction of their inorganic chemistry knowledge framework.Y3 Fe5 O12 nanopowder with a garnet structure was synthesized via the sol-gel method,and then characterized by using scanning electron microscopy(SEM),variable-temperature X-ray powder diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible absorption spectroscopy(UV-Vis).Combined with the interesting observation and quantitative analysis of reversible thermochromic phenomena in pre-patterned ceramic plate,the temperature dependence of the unit cell parameters was established and further elucidated how structural modulation affects d-d transitions and charge transfer,thereby summarizing the generation mechanism of the specific colors presented at different temperatures.This process fosters a more systematic and concrete understanding of crystal field theory and related concepts,ultimately enabling students to deeply internalize the core chemical principle of"structure determines properties".Compared with existing color-display experiments,the innovation lies in dynamically presenting the reversible thermochromism through lattice expansion,the selected garnet model has both tetrahedral and octahedral structural units,and its color-changing mechanism involves both d-d transitions and charge transfer.Moreover,embedding the thermochromic pigment in ceramics has application prospects such as temperature measurement and indication.This approach of"applying learning to practice"aims to enhance teaching and learning enjoyment,potentially stimulating students'innovative potential and enthusiasm for exploration.关键词
晶体场理论/热致变色/电荷转移/d-d跃迁/石榴石结构Key words
Crystal field theory/Thermochromism/Charge transfer/d-d transitions/Garnet structure分类
化学化工引用本文复制引用
吴小峰,王珊,袁龙,侯长民..科教融合科研训练实验设计:晶体场理论下的钇铁石榴石热致变色[J].应用化学,2025,42(11):1550-1558,9.基金项目
吉林大学2024年研究生教育教学改革研究项目(No.2024JGY017)和吉林省高等教育教学改革研究课题(No.JLJY202329642179)资助 Supported by Jilin University 2024 Graduate Education Reform Research Project(No.2024JGY017)and Jilin Province Higher Education Teaching Reform Research Project(No.JLJY202329642179) （No.2024JGY017）
