Unexpected structural/motional mode of water intercalated into an α‐crystalline zirconium phosphate deduced by 31P and 2H solid‐state MAS NMR spectra. (18th October 2021)

• Record Type: Journal Article
• Authors: Bakhmutov, Vladimir I.; Contreras‐Ramirez, Aida; Banerjee, Sayan; Zhou, Hong‐Cai
• Is Part Of: Magnetic resonance in chemistry. Volume 60:Number 2(2022)
• Page Start: 189
• Page End: 195
• Publication Date: 2021-10-18
• Subjects: dynamics -- NMR -- relaxation -- structural elucidation -- zirconium phosphates; Nuclear magnetic resonance spectroscopy -- Periodicals; Chemistry, Organic -- Periodicals; Magnetic resonance -- Periodicals; 538.36
• DOI: 10.1002/mrc.5225
• Languages: English
• ISSNs: 0749-1581

Abstract

Abstract: In developing the approach to understanding dynamics of intercalates in layered materials, crystalline‐layered zirconium phosphate Zr (HPO4 )2 ·0.35D2 O has been prepared and characterized by the 1 H, 31 P, and 2 H solid‐state MAS NMR spectra, including 31 P and 2 H T1 measurements. At temperatures >253 K, the intercalated water shows two spectrally‐distinguished deuterons unprecedentedly with different DQCC's and 2 H T1 times, one of which is hydrogen bonded. The collected data allowed to identify an unexpected bonding/dynamic mode of water molecules, which experience fast rotation around the hydrogen bond, formed with a zirconium‐coordinated oxygen. The low‐temperature 2 H MAS NMR experiments have demonstrated the presence of additional hydrogen bond P(H)O˙˙˙ DO, population of which grows on cooling to 195 K corresponding to the doubly hydrogen‐bonded immobile water molecule. Abstract : The 1 H, 31 P, and 2 H solid‐state MAS NMR experiments, including 31 P and 2 H T1 measurements, have resulted in establishment of an unexpected state of water showing two spectrally distinguished deuterons, unprecedentedly, with different DQCC's and 2 H T1 times, one of which is hydrogen bonded.