摘要
The present paper reports the spectroscopic investigations on non-covalent interaction of fullerenes C60 and C70 with a designed trihomocalix[6]arene (rong class="boldFont">2rong>) in toluene. UV-vis studies reveal appreciable ground state interaction between fullerenes and rong class="boldFont">2rong>. Jobs method of continuous variation establishes 1:1 stoichiometry for fullerene-rong class="boldFont">2rong> complexes. Binding constant (K) data reveals that rong class="boldFont">2rong> binds C70 more strongly compared to C60, i.e. KC60-rong class="boldFont">2rong> = 47,540 dm3 mol鈭? and KC70-rong class="boldFont">2rong> = 86,360 dm3 mol鈭?. Proton NMR studies provide very good support in favor of strong binding between C70 and rong class="boldFont">2rong>. Estimation of solvent reorganization energy (RS) evokes that C70-rong class="boldFont">2rong> complex is stabilized more compared to C60-rong class="boldFont">2rong> complex as RS(C60-rong class="boldFont">2rong>) = 鈭?.162 eV and RS(C70-rong class="boldFont">2rong>) = 鈭?.244 eV. Semiempirical calculations at third parametric level of theory in vacuo evoke the single projection structures of the fullerene-rong class="boldFont">2rong> complexes and interpret the stability difference between C60 and C70 complexes of rong class="boldFont">2rong> in terms of enthalpies of formation values.