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By the reaction of MnII(salen) (salen=N,N′-ethylenebis(salicylideneiminato) dianion) and its analogues with molecular oxygen in organic solvents, three types of complexes including as structural units the MnIII–O2–MnIII,–(–MnIV–O–)–n, and MnIV=O bonds respectively, have been obtained, and characterized by means of their electronic and infrared spectra, by thermogravimetric analysis, and in terms of their magnetic properties. The lower magnetic moments for [MnIII(salen)]2O2 and –[–MnIV(salen)–O–]–n than those expected have been interpreted in terms of antiferromagnetic interactions. The oxo complex was found to give the catena-oxo complex quantitatively in a DMF, DMSO, or Py solution. The effects of the oxygen partial pressure and the nature of the substituent in the organic part on the complex formation were investigated. A lower partial pressure of oxygen has the advantage of yielding the μ-peroxo complex in a higher yield. A discussion of the reaction mechanism is also included.

We have conducted this study to find an equation that is capable of predicting the temperature distribution in a semi-infinite phase change material (PCM) that has broad phase-change-temperature range on the condition that the initial temperature distribution is uniform at a lower temperature than the phase-change-temperature, and the surface is kept at a higher temperature than the phase-change-temperature. We found that the temperature distribution in the PCM with broad phase-change-temperature range can be approximated by substituting the lower inflection point temperature of the Gaussian distribution of the apparent specific heat for the phase-change-temperature in the equations that express temperature distribution in the PCM with a specific phase-change-temperature.

18- and 22-membered tetraaza macrocycles were prepared from acetylacetone and 1,4-diaminobutane or 1,6-diaminohexane, respectively. Their copper(II) complexes were characterized by electronic spectroscopy and the copper(II) complex of the 18-membered macrocycle was found to be pseudo-tetrahedral.

The polymeric Mn(III) Schiff base complexes react with superoxide ions (O2−) in dimethyl sulfoxide (DMSO) to give the oxygenated complexes, while the corresponding monomeric Mn(III) complexes are reduced with O2− to the Mn(II) complexes.