title: Crystal structure of the thermochromic bis-(di-ethyl-ammonium) tetra-chlorido-cuprate(II) complex.
abstract: In the structure of the title complex salt, (Et2NH2)2[CuCl4], the asymmetric unit consists of four unique di-ethyl-ammonium cations and three unique tetra-chlorido-cuprate anions. Two of the three anions are located with their copper atoms on independent crystallographic twofold axes, while the remaining tetra-chlorido-cuprate is located at a general position of the ortho-rhom-bic space group P21212. Two of the three Cu atoms adopt a distorted square-planar/disphenoidal geometry and the third Cu atom has a regular square-planar coordination environment. The di-ethyl-ammonium cations form an extensive hydrogen-bonded network through N-H⋯Cl inter-actions with the tetra-chlorido-cuprate anions, resulting in a two-dimensional sheet-like hydrogen-bonded network parallel to the ab direction. The complex was observed to undergo a color shift from deep green at room temperature to pale yellow at temperatures above 328 K.
authors: Department of Chemistry & Physics, Saint Mary's College, Notre Dame, IN 46556, USA.
authors: Emily P
authors: EP
authors: Aldrich
authors: Department of Chemistry & Physics, Saint Mary's College, Notre Dame, IN 46556, USA.
authors: Katherine A
authors: KA
authors: Bussey
authors: Department of Chemistry & Physics, Saint Mary's College, Notre Dame, IN 46556, USA.
authors: Jennifer R
authors: JR
authors: Connell
authors: Department of Chemistry & Physics, Saint Mary's College, Notre Dame, IN 46556, USA.
authors: Erin F
authors: EF
authors: Reinhart
authors: Department of Chemistry & Physics, Saint Mary's College, Notre Dame, IN 46556, USA.
authors: Kayode D
authors: KD
authors: Oshin
authors: Department of Chemistry, Yale University, New Haven, CT, 06520, USA.
authors: Brandon Q
authors: BQ
authors: Mercado
authors: Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
authors: Allen G
authors: AG
authors: Oliver
keywords: crystal structure; four-coordinate copper(II) complex; thermochromism