{Bis(N,N-di­methyl­form­amide)[μ-N,N′-bis­(salicyl­idene)-1,3-propane­diaminato]­nickel(II)}dibromozinc(II)

The title compound, [NiZnBr₂(C₃H₇NO)₂(C₁₇H₁₆N₂O₂)], is a heterodinuclear nickel complex. The Ni atom has an irregular octahedral environment involving two O and two N atoms from the bis­(salicyl­idene)-1,3-propane­diaminate ligand in the equatorial plane, and two O atoms from the di­methyl­form­amide groups. The Zn—O—Ni, O—Zn—O, Ni—O—Zn and O—Ni—O angles in the bridged plane are 100.1 (2), 79.9 (2), 100.4 (2) and 78.89 (17)°, respectively. The Ni⃛Zn distance is 3.0738 (19) Å.     

On moving continua with contacts and sliding friction: Modeling,general properties and examples

Many technical applications feature contacts between moving continua, where the contact zone is more or less spatially fixed. This contribution describes the modeling of such systems by means of weak formulations derived from Hamilton’s Principle in a material as well as a spatial formulation. Furthermore, linearizations about a stationary solution are carried out, the arising differential operators are stated and discussed with respect to symmetry. Particular attention is paid to the structure and physical interpretation of the contributions arising from the contacts as well as those due to the transport motion. The article closes with several examples.     

Poly­[methyl­ammonium tris(μ2‐form­ato‐κ2O:O′)­cobalt(II)]

The structure of the title compound, {(CH₆N)[Co(CHO₂)₃]}_n, consists of a three‐dimensional net of central Co^II ions connected via formate (methane­diolate) bridges. The negative charge is compensated by protonated methyl­amine cations. The CoO₆ chromophores form slightly distorted octahedra, which are bridged by C atoms of formate groups. The central Co atom lies on an inversion center and most of the other atoms lie on an m plane.