Öppna denna publikation i ny flik eller fönster >>2007 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]
This thesis is focused on the synthesis and structural determination of a series of quasicrystal approximants in the RE13Zn~58 (RE = Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu), Ce13Cd~58 and RECd6 (RE = Tb, Ho, Er, Tm and Lu) systems. Structural studies were performed by single crystal X-ray diffraction methods.
The RECd6 phases are 1/1 cubic approximants to the stable icosahedral quasicrystals. The structure of quasicrystals cannot be solved by conventional crystallography due to the lack of periodicity in three-dimensional space. On the other hand, quasicrystal approximants exhibit long-range order, which makes their structural determination possible by standard methods. Since they are believed to display the same local arrangement as the quasicrystals, the structures of the quasicrystal approximants play a key role in understanding quasicrystals.
The RE13Zn~58 and Ce13Cd~58 quasicrystal approximants show measurable compositional variations coupled to subtle structural differences. The crystal structures are generally rather more complex than previously reported, and exhibit a number of different ordering and disordering modes.
Ort, förlag, år, upplaga, sidor
Stockholm: Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi, 2007. s. 82
Nyckelord
Rare-earth, Quasicrystal approximant, order and disorder
Nationell ämneskategori
Kemi
Forskningsämne
oorganisk kemi
Identifikatorer
urn:nbn:se:su:diva-7203 (URN)978-91-7155-515-1 (ISBN)
Disputation
2007-12-19, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 12 A, Stockholm, 10:00
Opponent
Handledare
2007-11-282007-11-21Bibliografiskt granskad