Disorder and polymorphism in Cu(ii)-polyoxometalate complexes: [Cu1.5(H2O)7.5PW12O40]·4.75H2O, cis- & trans-[Cu2(H2O)10SiW12O40]·6H2O. Issue 28 (3rd June 2016)

• Record Type: Journal Article
• Authors: Bajpe, Sneha R.; Henke, Sebastian; Lee, Jung-Hoon; Bristowe, Paul D.; Cheetham, Anthony K.
• Is Part Of: CrystEngComm. Volume 18:Issue 28(2016)
• Page Start: 5327
• Page End: 5332
• Publication Date: 2016-06-03
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/c5ce02088c
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : Three highly crystalline Cu(ii )-polyoxometalate (POM) complexes, [Cu1.5 (H2 O)7.5 PW12 O40 ]·4.75H2 O and cis - and trans -[Cu2 (H2 O)10 SiW12 O40 ]·6H2 O, were successfully synthesized and characterized by single crystal and powder X-ray diffraction as well as thermogravimetric analysis. Abstract : Three highly crystalline Cu(ii )-polyoxometalate (POM) complexes, [Cu1.5 (H2 O)7.5 PW12 O40 ]·4.75H2 O and cis - and trans -[Cu2 (H2 O)10 SiW12 O40 ]·6H2 O, were successfully synthesized and characterized by single crystal and powder X-ray diffraction as well as thermogravimetric analysis. All complexes feature octahedrally coordinated, Jahn–Teller-distorted Cu II centres, which are coordinated by one terminal oxygen atom of the POM anion and five water molecules. The crystal structure of [Cu1.5 (H2 O)7.5 PW12 O40 ]·4.75H2 O, reveals four-fold disorder at one of the two Cu-sites, whereas [Cu2 (H2 O)10 SiW12 O40 ]·6H2 O crystallizes in two fully-ordered polymorphic forms: a monoclinic structure containing an angled cis configuration of the Cu-POM-Cu molecule and a triclinic structure containing a linear trans configuration. Density functional theory (DFT) calculations show that the cis polymorph of [Cu2 (H2 O)10 SiW12 O40 ]·6H2 O is more stable than the trans form by about 30 kJ mol −1 .