English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The title compounds have been prepared by reactions of the metal acetates of zink, cadmium, and mercury with ethanolic solutions of sodium polyselenides in the presence of 15-crown-5. They form dark red crystals, which were characterized by their IR specta as well as by X-ray crystal structure determinations. All complexes [Na-15-crown-5] 2 [M(Se  4 ) 2 ] with M = Zn (1), Cd (2), Hg (3) crystallize isotypically in the space group C2/c with 4 formula units per unit cell. In the anions [M(Se 4 ) 2 ] 2-  the metal atoms are coordinated tetrahedrally by four selenium atoms of two Se 4  2-  units, thus forming a spiro-bicyclus. The complex cations [Na-15-crown-5] +  have a Na---Se contact of approximately 299 pm with two selenium atoms of a MSe 4  group, allowing formulation of triple ion species.

Synthese und Kristallstrukturen der spirocyclischen Polyselenido-Komplexe [Na-15-Krone-5] 2 [M(Se 4 ) 2 ] mit M = Zink, Cadmium und Quecksilber