Study of the relationship between structure and O-17 electric field gradient parameters in some aluminosilicates
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Tarih
2005
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
World Scientific Publ Co Pte Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The relation between O-17 quadrupolax parameters and the local structure in silicates is of considerable interest if these parameters are to be used as a local probe. Although there are a number of investigations and some theoretical work on Si-O-Si bonds, there seems to be very little experimental data on Si-O-Al bonds. We have therefore investigated a number of sodalites with a general formula of M-8[AlSiO4]Cl-2 where M is an alkali cation. They have only one oxygen site and a Si:Al ratio of one. By varying the alkali we were able to change the Si-O-Al bond angle about five degrees steps from 125 to 152 degrees. The value of the electric field gradient (EFG), C-Q of O-17, followed a roughly similar angular dependence to that found for Si-O-Si bonds with C-Q180 = 4.2 MHz. The asymmetry parameter of O-17 also behaved in a similar fashion to that found for Si-O-Si bonds although it increased more rapidly at small angles.
Açıklama
dupree, ray/0000-0002-3334-0429
Anahtar Kelimeler
O-17NMR, quadrupole coupling constant, asymmetry parameter
Kaynak
Modern Physics Letters B
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
19
Sayı
24
Künye
closedAccess
