高煤级煤—隐晶质石墨的Raman光谱表征及结构演化

拉曼光谱能够反映碳材料结构的有序程度和结构缺陷，可用来表征高煤级煤—隐晶质石墨演化过程中结构变化。通过对受岩浆热变质影响的不同变形变质程度样品的拉曼参数与面网间距（d₀₀₂）之间关系的研究表明:G峰位置与d₀₀₂呈现阶梯变化，能较好地区分出石墨与高煤级煤，S₂峰位、D₁、G半峰宽与d₀₀₂呈较好的线性关系；D₁与G峰峰位差和半峰宽比随d₀₀₂减小而减小，S₂与S₄峰的峰位差随d₀₀₂减小先增大后减小，而其强度比及面积比逐渐增大；d₀₀₂与拉曼参数关系显示两次明显的结构演化跃变，即无烟煤至变质无烟煤阶段，R_max>6.5%、P（D₁-G）<235 cm-1、P（S₂-S₄）>525 cm-1以及半峰宽比显著下降、L_a/L_c迅速降低，为芳构化、芳环缩合作用增强向芳环叠片拼叠转变；半石墨至石墨演化阶段，P（D₁-G）、I_D1/I_G与A_D1/A_G显著降低，L_a、L_c迅速增加。以d₀₀₂为标度能较好地反映煤结构在不同演化阶段的Raman光谱特征。 

Raman spectrum characteristic and structural evolution of high rank coalscryptocrystalline graphite

Raman spectroscopy can reflect the order degree and structural defects of carbon materials,and can be used to characterize the structural changes during the evolution of high rank coal-cryptocrystalline graphite,and analyze the relationship between Raman parameters of coal with different deformation and metamorphic degrees and the spacing of surface network(d002).The results showed that:(1)there was stepped variation between the G peak position and d002,but the graphite and high rank coal could be distinguished well.The S2 peak,the full width at half maximum of D1 and G had a good linear relationship with d002;(2)the peak difference between D1 and G and the full width at half maximum ratio decreased with the decrease of d002:the peak difference between S2 and S4 increased first and then decreased with the decrease of d002,while the intensity ratio and area ratio increased gradually;(3)the relationship of interlayer spacing(d002)and Raman parameters figure shows the structure of two obvious evolutionary step,namely anthracite to ultra-anthracite(Rmax>6.5%,P(D1-G)<235 cm^-1,P(S2-S4)>525 cm^-1 and half peak width ratio dropped significantly,La/Lc reduce 2-3 times),semi-graphite to graphite evolutionary stages(P(D1-G),ID1/IG,AD1/AG significantly reduced;La,Lc increase rapidly).The Raman spectral characteristics of coal structure at different evolution stages can be well reflected by taking d002 as the scale.