Abstract Electronic interactions in donor-π-linker-acceptor systems with barbituric acid as an electron acceptor and possible donor were investigated to screen promising candidates a push–pull character based on experimental quantum chemical studies. The tautomeric properties of 5-benzylidenebarbituric derivatives studied NMR spectra, spectrophotometric determination the pKa values, calculation...

in this paper, we investigate various kinds of extensions of twin-good rings. moreover, we prove that every element of an abelian neat ring r is twin-good if and only if r has no factor ring isomorphic to z2  or z3. the main result of [24] states some conditions that any right self-injective ring r is twin-good. we extend this result to any regular baer ring r by proving that every element of a...

Stereoelectronic effects modulate molecular structure, reactivity, and conformation. We find that the interaction between the ester and carboxyl moieties of aspirin has a previously unappreciated quantum mechanical character that arises from the delocalization of an electron pair (n) of a donor group into the antibonding orbital (π*) of an acceptor group. This interaction affects the physicoche...

A class of bis(phenothiazine)arene dications were isolated and structurally characterized by using weakly coordinating anions. Their electronic structures were investigated by various experiments in tandem with DFT calculations. They all feature singlet ground states with a considerable diradical character and may be regarded as nearly pure diradicals. Our work demonstrates the important role o...

Let ∆(Πn) denote the order complex of the partition lattice. The natural Sn-action on the set [n] induces an Sn-action on ∆(Πn). We show that the regular CW complex ∆(Πn)/Sn is collapsible. Even more, we show that ∆(Πn)/Sn is collapsible, where Π∆ is a suitable type selection of the partition lattice. This allows us to generalize and reprove in a conceptual way several previous results regardin...

In this paper, we consider lifts of π-partial characters with the property that the irreducible constituents of their restrictions to certain normal subgroups are also lifts. We will show that such a lift must be induced from what we call an inductive pair, and every character induced from an inductive pair is a such a lift. With this condition, we will get a lower bound on the number of such l...