Study of N—H Frequencies in Some Metal-Halide Chelates of O-Phenylenediamine
The infrared studies in connection with the bidentate complexes of o-phenylenediamine were directed toward the study of N–H vibrations. Similar investigations have been undertaken with regard to the N–H stretching and bending vibrations of aniline and α-naphthylamine. Deuteration studies were made. As a result of these studies and by comparison with the assignment of frequencies made in the above mentioned investigations, stretching, scissors, and wagging frequencies are assigned to the chelates of o-phenylenediamine. The absorption in the region of ND2 wagging vibrations of the deuterated palladium complex failed to show splitting and therefore coupling with the C–H out-of-plane vibrations, as was evident in the spectra of the corresponding complexes of α-napthylamine and aniline.
An experimental investigation of impact ionization by electroluminescence in composite channel lattice-matched InAlAs/InGaAs/InP/InAlAs high electron mobility transistors (HEMTs) is presented. In these transistors, an InP subchannel layer is added to the InGaAs channel. Radiative recombinations at two different energies are observed, characteristic of recombinations in the InGaAs channel and at the InP/AlInAs interface. The bias-dependent electroluminescence line intensities are used to analyze the role played by the InP layer for relaxing the hot carriers. A large fraction of electrons in the InGaAs channel of the composite HEMT is transferred to the InP subchannel in the high field gate-drain region.