title: Absorption spectrophotometric, NMR and theoretical investigations on ground state non-covalent interaction of C₆₀ and C₇₀ with a designed trihomocalix[6]arene in solution.
abstract: The present paper reports the spectroscopic investigations on non-covalent interaction of fullerenes C(60) and C(70) with a designed trihomocalix[6]arene (2) in toluene. UV-vis studies reveal appreciable ground state interaction between fullerenes and 2. Jobs method of continuous variation establishes 1:1 stoichiometry for fullerene-2 complexes. Binding constant (K) data reveals that 2 binds C(70) more strongly compared to C(60), i.e. K(C60-2)-47,540 dm(3)mol(-1) and K(C70-2)-86,360 dm(3)mol(-1). Proton NMR studies provide very good support in favor of strong binding between C(70) and 2. Estimation of solvent reorganization energy (R(S)) evokes that C(70)-2 complex is stabilized more compared to C(60)-2 complex as R(S(C60-2))- -1.162 eV and R(S(C70-2))- -1.244eV. Semiempirical calculations at third parametric level of theory in vacuo evoke the single projection structures of the fullerene-2 complexes and interpret the stability difference between C(60) and C(70) complexes of 2 in terms of enthalpies of formation values.
authors.affiliation: Department of Chemistry, The University of Burdwan, Golapbag, Burdwan 713 104, India.
authors.forename: Amal
authors.initials: A
authors.lastname: Halder
authors.forename: Kshama
authors.initials: K
authors.lastname: Kundu
authors.forename: Sandip K
authors.initials: SK
authors.lastname: Nayak
authors.forename: Subrata
authors.initials: S
authors.lastname: Chattopadhyay
authors.forename: Sumanta
authors.initials: S
authors.lastname: Bhattacharya
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010636:Phenols / Q000737:chemistry*; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D037741:Fullerenes; D010636:Phenols; C476540:calix(6)arene; D047250:Calixarenes