Dependence of the fundamental absorption edge of CdInGaS4 on hydrostatic pressure

The optical absorption of CdInGaS₄ single crystals has been measured over a hydrostatic pressure range up to 40 kbar in the 2.0–3.0 eV photon energy range at room temperature. The interband gap for the indirect allowed transition was found to have a pressure coefficient, dEg/dP, of +6.4 × 10^-6ev/bar.     

The Bethe Equation at q = 0, The Möbius Inversion Formula,and Weight Multiplicities: III. The X

It is shown that the numbers of off-diagonal solutions to the U _q (X ^(r) _N ) Bethe equation at q = 0 coincide with the coefficients in the recently introduced canonical power series solution of the Q-system. Conjecturally, the canonical solutions are characters of KR (Kirillov–Reshetikhin) modules. This implies that the numbers of off-diagonal solutions agree with the weight multiplicities, which is interpreted as a formal completeness of the U _q (X ^(r) _N ) Bethe ansatz at q = 0.     

Photodimerization of 1,4-dicinnamoylbenzene crystal via a topochemical process

1,4-Dicinnamoylbenzene crystals photodimerize readily via a double [2+2] cycloaddition into the corresponding tricyclic dimer, which consists of two cyclobutane rings and a macro ring bridged by two phenylene linkages.     

Photoluminescence of the layered compound CdInGaS4

Summary The photoluminescence of the layered compound CdInGaS₄ was measured and analysed. The broad emission band at about 1.95 eV was found to be composed of three bands peaking at 2.16, 1.98 and 1.76 eV at 4.8K. These bands are due to free-to-bound or donor-to-acceptor transitions. We have found a new emission band peaking at 2.38 eV. This band shows that peak intensity markedly depends on the position in the crystal and is related to localized centres. The origin of the centres is discussed. Paper presented at the ?V International Conference on Ternary and Multinary Compounds?, held in Cagliari, September 14–16, 1982.     

Heat exchange type of titration calorimetry with on-line analogue compensation for the effect of titrant addition

A theoretically exact method of compensation for the effect of titrant addition is developed for the previously reported heat exchange type of calorimetry. An adequate modification is made on the calorimeter vessel, covering a part of the heat exchanger surface for thermal insulation, to make the relevant differential equations simpler. The differential equations are realized in the form of an operational amplifier circuit, where the resistance of a variable resistor increases in parallel with the movement of the piston of a burette. The effect of titrant addition at a rate up to 7 cm³ min^?1 can be completely compensated. For illustration the heat of reaction of THAM with a standard HCl solution is estimated in a titrimetric procedure and a satisfactory result is obtained.