Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Structural Studies of NaPO3-AlF3 Glasses by High-Resolution Double-Resonance Nuclear Magnetic Resonance Spectroscopy
Δημιουργός/Συγγραφέας:	Bradtmüller H. Zhang L. De Araujo C.C. Eckert H. Möncke D. Ehrt D.
Εκδότης:	American Chemical Society
Ημερομηνία:	2018
Γλώσσα:	Αγγλικά
ISSN:	1932-7447
DOI:	10.1021/acs.jpcc.8b06162
Περίληψη:	The local structure of the model glasses (NaPO3)1-x-(AlF3)x (0 ≤ x ≤ 0.4), prepared by standard melt-cooling, was extensively investigated by high-resolution solid-state nuclear magnetic resonance (NMR) including advanced double-resonance techniques. This glass system offers the opportunity of studying five different heteronuclear distance correlations (Na-F, Na-P, P-F, Al-F, and P-Al) by 10 distinct double-resonance experiments, involving all of the constituent elements present. 27Al MAS-NMR data indicate that aluminum is predominantly six-coordinated. According to 27Al{31P} and 27Al{19F} rotational-echo double-resonance (REDOR) spectroscopic results, two to three Al-F and three to four Al-O-P linkages occur in these glasses, independent of composition x. 19F MAS-NMR spectra show the presence of terminal P-bound and Al-bound fluorine species. A small amount of fluorine bridging to two aluminum octahedra, which could be assigned based on 19F{27Al} and 19F{31P} REDOR experiments, was also detected. 19F{23Na} REDOR experiments indicate that the Al-bound terminal F atoms interact significantly more strongly with sodium ions than the P-bonded terminal F atoms, which is consistent with local charge considerations. On the basis of the detailed quantitative dipole-dipole coupling information obtained, a comprehensive structural model for these glasses is presented.
Τίτλος πηγής δημοσίευσης:	Journal of Physical Chemistry C
Τόμος/Κεφάλαιο:	122
Τεύχος:	37
Σελίδες:	21579-21588
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry [EL] Φασματοσκοπία[EN] Spectroscopy
Αξιολόγηση από ομότιμους (peer reviewed):	Ναι
Κάτοχος πνευματικών δικαιωμάτων:	© 2018 American Chemical Society.
Σημειώσεις:	Natural Resources Wales, NRW; Deutsche Forschungsgemeinschaft, DFG: Ec168/3-1, Ec168/4-2, SFB458; Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP: 2017/029536 Financial support from Deutsche Forschungsgemeinschaft (grants Ec168/3-1 and Ec168/4-2) is gratefully acknowledged. C.C.d.A. thanks the NRW Graduate School of Chemistry for a personal stipend, and L.Z. thanks the DFG (via SFB458) for the support as a visiting scientist to the University of Münster. H.E. and H.B. thank FAPESP, process number 07793-6 (CEPID program). D.M. thanks FAPESP (process number 2017/029536) for the financial support of a research visit in 2017 at the Laboratório de Materiais Vit́ reos at the Departamento de Engenharia de Materiais, Universidade Federal de Saõ Carlos, Brazil.
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο