Two new chiral Schiff base acacen-derivative nickel(II) and copper(II) complexes have been prepared and characterized with IR, electronic, and CD spectra and X-ray crystallography. So-called artifact peaks of soli...Two new chiral Schiff base acacen-derivative nickel(II) and copper(II) complexes have been prepared and characterized with IR, electronic, and CD spectra and X-ray crystallography. So-called artifact peaks of solid-state CD spectra due to restricted to rotate freely of molecules appeared at about 334 and 460 nm for nickel(II) and copper(II) complexes. Changes of intensity of the peaks have been investigated in different matrices such as solid-state (microcrystals or KBr pellets), PMMA cast films and acetone solutions of various concentrations and pure acetone solutions. Although restricted orientation of molecules in rigid matrices leads to increase the peak intensity toward negative and positive optical rotation for nickel(II) and copper(II) complexes, respectively, the degree of increasing intensity depends on not concentration but viscosity of polymer solutions. Therefore, the artifact CD peaks of solid-state can act as an indicator of environmental viscosity of soft mater matrices.展开更多
A mononuclear chiral copper(ll) complex, [Cu(RRchxn)2(C(CN)3)2]'H20 (RRchxn = (1R, 2R)-diaminocyclohexane) (RRchxnH), and its deuterated compound, [Cu(RRchxn)2(C(CN)3)z].D20 (RRchxnD), and their...A mononuclear chiral copper(ll) complex, [Cu(RRchxn)2(C(CN)3)2]'H20 (RRchxn = (1R, 2R)-diaminocyclohexane) (RRchxnH), and its deuterated compound, [Cu(RRchxn)2(C(CN)3)z].D20 (RRchxnD), and their isomers, [Cu(trchxn)2(C(CN)3)2]'H20 (trchxn = trans-l,2-diaminocyclohexane) (trchxnH) and [Cu(trchxn)2(C(CN)3)2]'D20 (trchxnD) have been prepared and characterized by means of 1R (infrared), electronic, and CD (circular dichroism) spectra, magnetic susceptibility, and variable-temperature X-ray crystallography as single crystals or powder. Interestingly, depending on grain size of samples, RRchxnH exhibits the monoclinic form and the orthorhombic form, which are distinguished by systematic absence and powder XRD (X-ray diffraction) patterns clearly. Although single crystals did not exhibit phase transition, powder XRD patterns of RRchxnH and weakly hydrogen bonded RRchxnD emerged low-temperature phase of monoclinic in the orthorhombic patterns only around 200-220 K. However, as a control, powder XRD patterns of both trchxnH and trchxnD did not exhibit such phase transition clearly.展开更多
The present paper describes the preparation of new organic reagent 2-[2-(6-chloro benzothiazolyl) azo]-resorcinol (6-CIBTAR = LH2) and used for the spectrophotometric determination of traces microgram amount of ni...The present paper describes the preparation of new organic reagent 2-[2-(6-chloro benzothiazolyl) azo]-resorcinol (6-CIBTAR = LH2) and used for the spectrophotometric determination of traces microgram amount of nickel (II) and copper (II) was found to form Ni(II)-CIBTAR at pH 7.5 giving a green coloured complex with maximum absorption at wavelength 636 nm and copper (II) was found to from Cu(II)-CIBTAR at pH 6.5 giving green bluish coloured complex with maximum absorption at wavelength 648 nm. The molar absorptivity (~) of the complexes are 0.3695 ~ 104 L.moll-cml and 0.3933 ~ 154 L'mol'l.cm1 for Ni(II) and Cu(II) respectively. Calibration curves for the determination of nickel(II) and copper (II) conformed to beers law over the concentration rang of (1-20) μg.mL-1. The DL (detection limit), RSD (relative standard deviations), RE (relative errors) and recovery for Ni(II) and Cu(II) complexes were found to be D.L = 0.45, 0.61; R.S.D% = 1.81, 2.04; Erei% = 1.3, 0.86 and Re% = 98.7, 99.14 respectively. The analytical data show the metal to reagent ratio (mole ratio method; M:L) in Ni(II) and Cu(II) complexes are 1:2.展开更多
文摘Two new chiral Schiff base acacen-derivative nickel(II) and copper(II) complexes have been prepared and characterized with IR, electronic, and CD spectra and X-ray crystallography. So-called artifact peaks of solid-state CD spectra due to restricted to rotate freely of molecules appeared at about 334 and 460 nm for nickel(II) and copper(II) complexes. Changes of intensity of the peaks have been investigated in different matrices such as solid-state (microcrystals or KBr pellets), PMMA cast films and acetone solutions of various concentrations and pure acetone solutions. Although restricted orientation of molecules in rigid matrices leads to increase the peak intensity toward negative and positive optical rotation for nickel(II) and copper(II) complexes, respectively, the degree of increasing intensity depends on not concentration but viscosity of polymer solutions. Therefore, the artifact CD peaks of solid-state can act as an indicator of environmental viscosity of soft mater matrices.
文摘A mononuclear chiral copper(ll) complex, [Cu(RRchxn)2(C(CN)3)2]'H20 (RRchxn = (1R, 2R)-diaminocyclohexane) (RRchxnH), and its deuterated compound, [Cu(RRchxn)2(C(CN)3)z].D20 (RRchxnD), and their isomers, [Cu(trchxn)2(C(CN)3)2]'H20 (trchxn = trans-l,2-diaminocyclohexane) (trchxnH) and [Cu(trchxn)2(C(CN)3)2]'D20 (trchxnD) have been prepared and characterized by means of 1R (infrared), electronic, and CD (circular dichroism) spectra, magnetic susceptibility, and variable-temperature X-ray crystallography as single crystals or powder. Interestingly, depending on grain size of samples, RRchxnH exhibits the monoclinic form and the orthorhombic form, which are distinguished by systematic absence and powder XRD (X-ray diffraction) patterns clearly. Although single crystals did not exhibit phase transition, powder XRD patterns of RRchxnH and weakly hydrogen bonded RRchxnD emerged low-temperature phase of monoclinic in the orthorhombic patterns only around 200-220 K. However, as a control, powder XRD patterns of both trchxnH and trchxnD did not exhibit such phase transition clearly.
文摘The present paper describes the preparation of new organic reagent 2-[2-(6-chloro benzothiazolyl) azo]-resorcinol (6-CIBTAR = LH2) and used for the spectrophotometric determination of traces microgram amount of nickel (II) and copper (II) was found to form Ni(II)-CIBTAR at pH 7.5 giving a green coloured complex with maximum absorption at wavelength 636 nm and copper (II) was found to from Cu(II)-CIBTAR at pH 6.5 giving green bluish coloured complex with maximum absorption at wavelength 648 nm. The molar absorptivity (~) of the complexes are 0.3695 ~ 104 L.moll-cml and 0.3933 ~ 154 L'mol'l.cm1 for Ni(II) and Cu(II) respectively. Calibration curves for the determination of nickel(II) and copper (II) conformed to beers law over the concentration rang of (1-20) μg.mL-1. The DL (detection limit), RSD (relative standard deviations), RE (relative errors) and recovery for Ni(II) and Cu(II) complexes were found to be D.L = 0.45, 0.61; R.S.D% = 1.81, 2.04; Erei% = 1.3, 0.86 and Re% = 98.7, 99.14 respectively. The analytical data show the metal to reagent ratio (mole ratio method; M:L) in Ni(II) and Cu(II) complexes are 1:2.