NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd

Kohn, S. C. ; Henderson, C. M. B. ; Dupree, R.
Springer
Published 1994
ISSN:
1432-2021
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Geosciences
Physics
Notes:
Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
Type of Medium:
Electronic Resource
URL:
_version_ 1798295902624940032
autor Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
autorsonst Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
book_url http://dx.doi.org/10.1007/BF00203148
datenlieferant nat_lic_papers
hauptsatz hsatz_simple
identnr NLM202916022
issn 1432-2021
journal_name Physics and chemistry of minerals
materialart 1
notes Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
package_name Springer
publikationsjahr_anzeige 1994
publikationsjahr_facette 1994
publikationsjahr_intervall 8009:1990-1994
publikationsjahr_sort 1994
publisher Springer
reference 21 (1994), S. 176-190
search_space articles
shingle_author_1 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
shingle_author_2 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
shingle_author_3 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
shingle_author_4 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
shingle_catch_all_1 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
1432-2021
14322021
Springer
shingle_catch_all_2 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
1432-2021
14322021
Springer
shingle_catch_all_3 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
1432-2021
14322021
Springer
shingle_catch_all_4 Kohn, S. C.
Henderson, C. M. B.
Dupree, R.
NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
Abstract A number of leucite group materials with the formula X2YSi5O12 where X=K, Rb, Cs and Y=Mg, Zn, Cd have been synthesized by dry and hydrothermal crystallization of glass starting materials. 29Si MASNMR has been used to obtain structural information, such as the number of distinct tetrahedral sites, degree of cation ordering, and estimates of the mean T-O-T bond angles of the tetrahedra. X-ray powder diffraction gave information on cell volumes and degree of distortion from cubic symmetry for all the samples and space group and structural information for some samples. Integration of the different length-scale data obtained using these two complementary techniques allows greater reliance to be placed on the structures deduced for these leucite samples, which are only available as fine-grained powders. Hydrothermally synthesized K2MgSi5O12, K2ZnSi5O12 and Rb2ZnSi5O12 have structures with 12 distinct tetrahedral sites (T-sites) and are monoclinic P21/c while the dry-synthesized equivalents are disordered with single T-sites and are cubic, Ia3d. Most of the other members of the group have structures with 6 tetrahedral sites with Cs2CdSi5O12 being orthorhombic, Pbca. Cs2ZnSi5O12 has an intermediate “5+2” structure. Decreasing the size of the X+ cation for a given Y2+ cation gives more collapsed and distorted frameworks. 133Cs NMR was used to show that samples with 6 T-sites have 2 alkali sites. It is deduced that samples with 12 T-sites will undergo a displacive phase transition to a 6 T-site structure (possibly via a 5+2 intermediate in some cases) with no change in the framework topology or degree of T-site ordering.
1432-2021
14322021
Springer
shingle_title_1 NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
shingle_title_2 NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
shingle_title_3 NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
shingle_title_4 NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
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source_archive Springer Online Journal Archives 1860-2000
timestamp 2024-05-06T09:43:35.326Z
titel NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
titel_suche NMR studies of the leucite analogues X2YSi5O12, where X= K, Rb, Cs; Y = Mg, Zn, Cd
topic V
TE-TZ
U
uid nat_lic_papers_NLM202916022