Metal-heptaiodide interactions in cyclomaltoheptaose (β-cyclodextrin) polyiodide complexes as detected via Raman spectroscopy

Charalampopoulos, VG; Papaioannou, JC; Kakali, G; Karayianni, HS

dc.contributor.author	Charalampopoulos, VG	en
dc.contributor.author	Papaioannou, JC	en
dc.contributor.author	Kakali, G	en
dc.contributor.author	Karayianni, HS	en
dc.date.accessioned	2014-03-01T01:28:46Z
dc.date.available	2014-03-01T01:28:46Z
dc.date.issued	2008	en
dc.identifier.issn	0008-6215	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18959
dc.subject	β-Cyclodextrins	en
dc.subject	Cyclomaltooligosaccharides	en
dc.subject	Disorder-order	en
dc.subject	Heptaiodide ions	en
dc.subject	Inclusion complexes	en
dc.subject	Raman spectroscopy	en
dc.subject.classification	Biochemistry & Molecular Biology	en
dc.subject.classification	Chemistry, Applied	en
dc.subject.classification	Chemistry, Organic	en
dc.subject.other	Band structure	en
dc.subject.other	Charge transfer	en
dc.subject.other	Ionic conduction	en
dc.subject.other	Molecular structure	en
dc.subject.other	Raman spectroscopy	en
dc.subject.other	Cyclomaltooligosaccharides	en
dc.subject.other	Heptaiodide ions	en
dc.subject.other	Inclusion complexes	en
dc.subject.other	Polyimides	en
dc.subject.other	barium	en
dc.subject.other	beta cyclodextrin	en
dc.subject.other	bismuth	en
dc.subject.other	cadmium	en
dc.subject.other	cesium	en
dc.subject.other	iodine derivative	en
dc.subject.other	lithium	en
dc.subject.other	metal	en
dc.subject.other	potassium	en
dc.subject.other	rubidium	en
dc.subject.other	sodium	en
dc.subject.other	sodium iodide	en
dc.subject.other	strontium	en
dc.subject.other	vanadium	en
dc.subject.other	article	en
dc.subject.other	carbohydrate analysis	en
dc.subject.other	chemical bond	en
dc.subject.other	cross linking	en
dc.subject.other	nonhuman	en
dc.subject.other	physical chemistry	en
dc.subject.other	priority journal	en
dc.subject.other	Raman spectrometry	en
dc.subject.other	room temperature	en
dc.subject.other	temperature sensitivity	en
dc.subject.other	thermal analysis	en
dc.subject.other	thermogravimetry	en
dc.subject.other	X ray crystallography	en
dc.subject.other	X ray powder diffraction	en
dc.subject.other	beta-Cyclodextrins	en
dc.subject.other	Cations	en
dc.subject.other	Iodides	en
dc.subject.other	Metals	en
dc.subject.other	Molecular Conformation	en
dc.subject.other	Spectrum Analysis, Raman	en
dc.subject.other	Temperature	en
dc.title	Metal-heptaiodide interactions in cyclomaltoheptaose (β-cyclodextrin) polyiodide complexes as detected via Raman spectroscopy	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.carres.2007.11.013	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.carres.2007.11.013	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The Raman spectra of the cyclomaltoheptaose (beta-cyclodextrin, beta-CD) polyiodide complexes (beta-CD)(2)center dot NaI7 center dot 12H(2)O, (beta-CD)(2)center dot RbI7 center dot 18H(2)O, (beta-CD)(2)center dot SrI7 center dot 17H(2)O, (beta-CD)(2)center dot BiI7 center dot 17H(2)O and (beta-CD)(2)-VI(7 center dot)14H(2)O (named beta-M, M stands for the corresponding metal) are investigated in the temperature range of 30 - 140 degrees C. At room temperature all systems show an initial strong band at 178 cm(-1) that reveals similar intramolecular distances of the disordered I-2 units (similar to 2.72 angstrom). During the heating process beta-Na and beta-Rb display a gradual shift of this band to the final single frequency of 166 cm(-1). In the case of beta-Sr and beta-Bi, the band at 178 cm(-1) is shifted to the final single frequencies of 170 and 172 cm(-1), respectively. These band shifts imply a disorder-order transition of the I-2 units whose I - I distance becomes elongated via a symmetric charge-transfer interaction I-2 <- I-3(-)-> I-2. The different final frequencies correspond to different bond lengthening of the disordered I-2 units during their transformation into well-ordered ones. In the Raman spectra of beta-V, the initial band at 178 cm(-1) is not shifted to a single band but to a double one of frequencies 173 and 165 cm(-1), indicating a disorder-order transition of the I-2 molecules via a non-symmetric charge-transfer interaction I-2 <- I-3(-)-> I-2. The above spectral data show that the ability of I-3(-) to donate electron density to the attached I-2 units is determined by the relative position of the different metal ions and their ionic potential q/r. The combination of the present results with those obtained from our previous investigations reveals that cations with an ionic potential that is lower than similar to 1.50 (Cs+, Rb+, Na+, K+ and Ba2+) do not affect the Lewis base character of I-3(-). However, when the ionic potential of the cation is greater than similar to 1.50 (Li+, Sr2+, Cd2+, Bi3+ and V3+), the Mn+center dot center dot center dot I-3(-) interactions become significant. In the case of a face-on position of the metal (Sr2+, Bi3+) relative to I-3(-) the charge-transfer interaction is symmetric. On the contrary, when the metal (Li+, Cd2+, V3+) presents a side-on position relative to I-3(-), the charge-transfer interaction is symmetric. On the contrary, when the metal (Li+, Cd2+, V3+) presents a side-on position relative to I-3(-), the charge-transfer interaction is non-symmetric. (c) 2007 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Carbohydrate Research	en
dc.identifier.doi	10.1016/j.carres.2007.11.013	en
dc.identifier.isi	ISI:000253667500009	en
dc.identifier.volume	343	en
dc.identifier.issue	3	en
dc.identifier.spage	489	en
dc.identifier.epage	500	en