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oder eine Originalarbeit ver- birgt. U. Krämer, Dresden Quasicrystals. A primer. By C. Janot. 2nd ed. Clarendon Press, Oxford 1994, XVI + 409 p. (ISBN 0-19-851778-5) £ 49.50. Despite the fact that quasicrystals have been definitely established as a new state ofmatter, since 1984, introductory courses as well as textbooks at an introductory level are still rarely found. This seems to be a consequence of the relatively high threshold between conventional and modern crystallo- graphy the latter making use of n-dimensional space. The present author meets these needs

Antiferromagnetism in two-dimensional quasicrystals Anuradha Jagannathan* and Attila Szallas Laboratoire de Physique des Solides, Bât.510, Université Paris-Sud 91405 Orsay, France Received June 12, 2008; accepted August 13, 2008 Quantum spins / Quasicrystals / Antiferromagnetism / Spin wave theory Abstract. Quasiperiodic structures possess long range po- sitional order, but are freed of constraints imposed by trans- lational invariance. For spins interacting via Heisenberg couplings, one may expect therefore to find novel magnetic configurations in such

Modulated quasicrystals Bernd Sing* Department of Mathematical Sciences, University of Bath, Claverton Down, BA2 7AY Bath, U.K. Received June 15, 2008; accepted July 21, 2008 Model sets / Modulation / Deformation Abstract. There is some confusion in the literature what “modulated quasicrystals” are: Some people treat “modu- lated quasicrystals” and “deformed model sets” as ex- changeable termini (compare [6, 9, 5]), others claim that “½. . . the projection method becomes powerless against incommensurate modulated structures” (e.g., [12 p. 148]). We use a

Optical response of si-ZnMgHo quasicrystal Vytautas Karpus*; I, Gintautas-Jurgis BabonasI, Alfonsas RėzaI, Saulius TumėnasI, Hans ArwinII, Wolf AssmusIII and Stefan BrühneIII I Semiconductor Physics Institute, A. Goštauto 11, 01108 Vilnius, Lithuania II Linköping University, Department of Physics, Chemistry and Biology, 58183 Linköping, Sweden III J. W. Goethe-Universität, Physikalisches Institut, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany Received June 14, 2008; accepted August 5, 2008 Quasicrystals / Spectroscopic ellipsometry / Dielectric

Anomalous conduction mechanisms of Al-based stable quasicrystals Ikuzo Kanazawa*, Hiroki Kitahata and Yuuki Sekiyama Department of Physics, Tokyo Gakugei University, Koganei-shi, Tokyo 184-8501, Japan Received June 15, 2008; accepted September 6, 2008 Quasicrystals / Conduction mechanism / Electron localization Abstract. We have analyzed the electrical conductivities of Al– Cu– Fe and Al– Cu– Ru quasicrystals in a low temperature region, taking into account the conducting mechanism of the quasicrystal-like system. The present analysis suggests strongly that not

Zeitschrift für Kristallographie 190, 179-234 (1990) © by R. Oldenbourg Verlag, München 1990 - 0044-2968/90 $3.00 + 0.00 The structure of quasicrystals Walter S teurer Institut für Kristallographie und Mineralogie der Universität, Theresienstraße 41, D-8000 München 2, Federal Republic of Germany Received: April 4, 1989; in revised form September 15, 1989 Quasicrystals / Crystal structure / Aperiodic crystals / nd Crystallography Abstract. The aim of the present article is to give a review of the state-of- the-art on quasicrystal structure analysis. After a short

Disorder in decagonal quasicrystals F. Frey* and E. Weidner Ludwig-Maximilians-Universität, Department für Geo- und Umweltwissenschaften, Sektion Kristallographie, Theresienstr. 41, D-80333 München, Germany Received September 18, 2002; accepted November 4, 2002 Abstract. Complementary neutron and x-ray diffuse scattering may provide insight into structural super-order- ing and disordering of decagonal quasicrystals (d-phases), and, in consequence, into the formation and stability of aperiodically ordered alloys. Neutron diffraction makes a contrasting almost

AlCoNi quasicrystal sphere growth experiment from a metallic solution Götz Meisterernst, Birgitta Bauer and Peter Gille* Department für Geo- und Umweltwissenschaften, Sektion Kristallographie, Ludwig-Maximilians-Universität, Theresienstraße, 41, 80333 München, Germany Dedicated to Professor Manfred Mühlberg on the occasion of his 60th birthday Received April 8, 2009; accepted July 7, 2009 Quasicrystal / Czochralski / Sphere growth Abstract. Crystal growth studies starting from spherical surfaces of single crystals can reveal morphological fea- tures that

Introduction The discovery of a synthetic alloy of aluminum and manganese with nearly point-like diffraction and axes of fivefold symmetry ( Shechtman et al. 1984 ) and the proposal of the quasicrystal theory to explain it ( Levine and Steinhardt 1984 ) shocked the worlds of crystallography and condensed matter physics. The laws of crystallography had been established since the nineteenth century. They had played a historic role in establishing the atomic theory, had represented the first compelling example of the power of group theory to explain physical

Diffuse and weak Bragg scattering from quasicrystals: pitfalls and opportunities Thomas Weber* and Walter Steurer Laboratory of Crystallography, Department of Materials, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland Received July 21, 2008; accepted August 18, 2008 Quasicrystals / Diffuse scattering / Disorder / Experimental artefacts Abstract. The influence of limited experimental recipro- cal space resolution on the appearance of diffraction pat- terns from quasicrystals is discussed. Using simulated data from a perfectly ordered one-dimensional Fibonacci