Na2MnSi4O10 has been hydrothermally synthesized from gel kept in a Teflonlined autoclave at 225C for 10 days. Its P1 crystal structure has been solved from singlecrystal X-ray diffraction data and anisotropically refined to R = 0.025. Being the structure isotypic with that of NaKMnSi4O10 (manaksite), it is referred to a manaksite-like cell (a = 6.946 A ° , b = 7.846 A ° , c = 9.974 A ° , a = 106.21, b = 98.54, c = 115.74) instead than to its reduced cell (a = 6.946 A ° , b = 7.846 A ° , c = 9.885 A ° , a = 101.94, b = 102.02, c = 115.74). The Na? cation corresponding to K? in manaksite is split on two positions. All known AA0MSi4O10 structures are triclinic, but show a strong monoclinic character. They are based on tubes delimited by elliptical six-membered rings of SiO4 tetrahedra and connected, to form a heteropolyhedral framework, by dimeric units consisting of two edge-sharing tetragonal pyramids of M-coordination polyhedra. A and A0 cations are located in the silicate tubes and in channels that are delimited by four tetrahedra and two dimeric units. The bottlenecks of tubes and channels are however, too narrow to define the structure as microporous.
Synthesis and crystal structure of Na2MnSi4O10 - Relationship with the manaksite group.
FERRARIS, Giovanni
2011-01-01
Abstract
Na2MnSi4O10 has been hydrothermally synthesized from gel kept in a Teflonlined autoclave at 225C for 10 days. Its P1 crystal structure has been solved from singlecrystal X-ray diffraction data and anisotropically refined to R = 0.025. Being the structure isotypic with that of NaKMnSi4O10 (manaksite), it is referred to a manaksite-like cell (a = 6.946 A ° , b = 7.846 A ° , c = 9.974 A ° , a = 106.21, b = 98.54, c = 115.74) instead than to its reduced cell (a = 6.946 A ° , b = 7.846 A ° , c = 9.885 A ° , a = 101.94, b = 102.02, c = 115.74). The Na? cation corresponding to K? in manaksite is split on two positions. All known AA0MSi4O10 structures are triclinic, but show a strong monoclinic character. They are based on tubes delimited by elliptical six-membered rings of SiO4 tetrahedra and connected, to form a heteropolyhedral framework, by dimeric units consisting of two edge-sharing tetragonal pyramids of M-coordination polyhedra. A and A0 cations are located in the silicate tubes and in channels that are delimited by four tetrahedra and two dimeric units. The bottlenecks of tubes and channels are however, too narrow to define the structure as microporous.
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