This article analyzes the electronic factors governing bond length alternation (BLA) in linear polyenes. The impact of various effects is illustrated on small all-trans polyenes, namely butadiene, hexatriene and octatetraene prototype molecules. It well known that self-consistent-field single determinant treatments overestimate paper aims to identify physical correlation which correct this defe...

The recent finding of a 1-bond→2-phonon behavior at the zone center in several A1−xBxC random zincblende mixed crystals, that mirrors a similar 1-bond→2-mode behavior in the bond length distribution, deviates strongly from the traditional 1-bond→1-mode (phonon, bond length) description of the local lattice relaxation in alloys, and thereby forces to rethink the scenario of spontaneous ordering ...

Bond-length distributions have been examined for 55 configurations of alkali-metal ions and 29 configurations of alkaline-earth-metal ions bonded to oxygen, for 4859 coordination polyhedra and 38 594 bond distances (alkali metals), and for 3038 coordination polyhedra and 24 487 bond distances (alkaline-earth metals). Bond lengths generally show a positively skewed Gaussian distribution that ori...

Polymer concrete, a composite material in which the binding material is some type of polymer, is being used more widely in the construction industry. Polymer concretes can also contain steel reinforcing rebars; therefore, the rate of adhesion between polymer concrete and reinforcing steel must be determined. Our study investigated the extent and behaviour of adhesion in the case of reinforcing ...