title: Measurement of circular birefringence and circular dichroism of the single crystals of lambda-(+)589- and delta-(-)589-tris(ethylenediamine)cobalt(III) triiodide monohydrate by the extended HAUP method.
abstract: We have achieved measuring four optical parameters simultaneously, namely, linear birefringence (LB), circular birefringence (CB), linear dichroism (LD), and circular dichroism (CD), of single crystals of Lambda-(+)(589)- and Delta-(-)(589)-tris(ethylenediamine) cobalt(III) triiodide monohydrate (1) along the <001> plane at the fixed wavelength (514.5 nm). Such measurements are possible only when the High Accuracy Universal Polarimeter (HAUP) is employed; it is called the extended HAUP method. Our experimental results showed that both LB and LD of the Lambda-(+)(589)-(1) crystal have the same magnitude as those of the Delta-(-)(589)-(1) crystal. It was also revealed for the first time that the CB data of crystals of Lambda-(+)(589)-(1) and Delta-(-)(589)-(1) are almost of the same magnitude, but are of opposite sign, reflecting their opposite absolute configurations. On the other hand, although the CD data obtained for Lambda-(+)(589)-(1) is almost three times larger than that for Delta-(-)(589)-(1,) these CD data are also opposite in sign, as expected from the opposite chirality of crystals. .
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Waseda University, Tokyo, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Matsuki
authors.forename: Toru
authors.initials: T
authors.lastname: Asahi
authors.forename: Jinzo
authors.initials: J
authors.lastname: Kobayashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Asai
mesh_terms: D016880:Anisotropy; D002942:Circular Dichroism / Q000379:methods*; D003035:Cobalt / Q000737:chemistry*; D003460:Crystallization; D005029:Ethylenediamines / Q000737:chemistry*; D007454:Iodides / Q000737:chemistry*; D008956:Models, Chemical; D009556:Niobium / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D013237:Stereoisomerism; D013696:Temperature
chemical_list: D005029:Ethylenediamines; D007454:Iodides; D009942:Organometallic Compounds; D010087:Oxides; D009556:Niobium; C091692:lithium niobate; C096699:tris(ethylenediamine)cobalt(III); D003035:Cobalt