Innenrücktitelbild: “114”-Type Nitrides LnAl(Si4−x Al x )N7 O δ with Unusual [AlN6 ] Octahedral Coordination (Angew. Chem. 14/2017)

A O(n8) X O(n7) Linear Programming Model of the Quadratic Assignment Problem

The Quadratic Assignment Problem (QAP) is the problem of making exclusive assignments of n indivisible entities to n other indivisible entities in such a way that a total quadratic interaction cost is minimized. The problem can be interpreted from a wide variety of perspectives. The perspective adopted in this paper is that of the generic facilities location/layout context, as in the seminal wo...

Approximating the Permanent in O∗(n7) Time

The first polynomial-time algorithm to approximate (with arbitrary precision) the permanent of a non-negative matrix was presented by Jerrum, Sinclair and Vigoda. They designed a simulated annealing algorithm with a running time of O∗(n26) for 0/1 matrices. Subsequently, they improved their analysis, resulting in a O∗(n10) time algorithm. We present a O∗(n7) time algorithm. Our improvement come...

An octahedral coordination complex of iron(VI).

The hexavalent state, considered to be the highest oxidation level accessible for iron, has previously been found only in the tetrahedral ferrate dianion, FeO4(2-). We report the photochemical synthesis of another Fe(VI) compound, an octahedrally coordinated dication bearing a terminal nitrido ligand. Mössbauer and x-ray absorption spectra, supported by density functional theory, are consistent...

An Unusual Type of O Agglutination.

Spotlights on our sister journals: Angew. Chem. Int. Ed. 15/2018.

MAC it happen : Presented is a study of the synergistic structuredirecting effect of metal–amine complexes (MACs) with different chelating polyamine ligands and imidazolium-based ionic liquid (IL) cations. For the first time, a layered selenidostannate with an asymmetric eight-membered ring, an organic-decorated layered selenidostannate, and a 3D selenidostannate with both the MAC and IL cation...