Rottstegge J, Hartwig H, Dreizler H
Institut für Physikalische Chemie, der Christian-Albrechts-Universität zu Kiel, Ludewig Meyn Str. 8, Kiel, D-24098, Germany
J Mol Spectrosc. 1999 May;195(1):1-10. doi: 10.1006/jmsp.1999.7802.
The microwave rotational spectrum of the p-fluorotoluene-argon van der Waals complex was analyzed with a molecular beam Fourier transform microwave spectrometer. In the frequency splitting of molecular transitions caused by the internal rotation of the methyl group with respect to the aromatic ring is contained the structure and barrier information. Elucidation is reduced by the analysis of internal rotors direction with respect to the principal axis system of the complex the number of possible solutions in the structure. An rs and r0 structure of the complex was calculated from these data. The argon is located 3.541(1) Å above the aromatic ring. By forming the complex, the barrier height of internal rotation is changed. An additional V3 term in the potential function occurs in the complex because the molecular symmetry of the p-fluorotoluene, containing a V6 but no V3 term, is reduced by the argon. For assumed V6 = 144.79(19) GHz or 57.777(76) J/mol, V3 is found to equal 552.0(10) GHz or 220.31(40) J/mol. Copyright 1999 Academic Press.
使用分子束傅里叶变换微波光谱仪分析了对氟甲苯 - 氩范德华复合物的微波转动光谱。在由甲基相对于芳环的内旋转引起的分子跃迁频率分裂中包含结构和势垒信息。通过分析内转子相对于复合物主轴系统的方向，减少了结构中可能解的数量。根据这些数据计算了复合物的(r_s)和(r_0)结构。氩位于芳环上方(3.541(1))Å处。通过形成复合物，内旋转的势垒高度发生变化。由于氩降低了含有(V_6)但没有(V_3)项的对氟甲苯的分子对称性，复合物的势函数中出现了一个额外的(V_3)项。对于假设的(V_6 = 144.79(19))GHz或(57.777(76))J/mol，发现(V_3)等于(552.0(10))GHz或(220.31(40))J/mol。版权所有1999年学术出版社。
