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Title: Emerging role of local and extended range molecular structures on functionalities of topological phases of (Na 2 O) x (P 2 O 5 ) 100‐ x glasses using Raman scattering and modulated DSC
Abstract

Raman scattering is a powerful probe oflocal structure (LS)of glasses. In Sodium Phosphate Glasses (SPGs), we show that bothLScomposed of Qnspecies andExtended Range Structures (ERS)composed of Long Chains (LCs), Large Rings (LRs), and Small Rings (SRs) can be decoded by Raman scattering. The trimodal distribution of P‐Oterminalstretch modes of Q2species and P‐Obridgingatx < 50% are manifestations of theseERS. These two pairs of triads of modes are uniquely identified with Q2units present in either LCs, or LRs, or SRs. The existence three phases of c‐NaPO3composed of 3‐membered rings, 6‐membered rings, and infinitely long chains has facilitated the identification. The Intermediate Phase (IP) in SPGs extends in the 37.5 < x < 46.0% range, the Stressed‐rigid Phase in the 46.0% < x < 50%, and the Flexible Phase in the 18% < x < 37.5% range of soda. We show the IP consists predominantly of LCs (82%), with a minority of LRs (15%) and SRs (3%). The LR‐ and SR‐fractions increase measurably in the non‐IP phases. The structural finding is in harmony with the high configurational entropy of the IP glasses that leads aging to be qualitatively suppressed.

 
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NSF-PAR ID:
10455191
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
International Journal of Applied Glass Science
Volume:
12
Issue:
1
ISSN:
2041-1286
Page Range / eLocation ID:
p. 89-110
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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