Influence of the ferroelastic twin domain structure on the 5100\ surface morphology of LaAlO3 HTSC substrates

Bueble, S.; Knorr, K.; Brecht, E. und Schmahl, Wolfgang W. (1998): Influence of the ferroelastic twin domain structure on the 5100\ surface morphology of LaAlO3 HTSC substrates. In: Surface Science, Vol. 400, No. 1-3: pp. 345-355

Abstract

LaAlO3 crystals have been investigated with differential scanningcalorimetry (DSC), high-precision X-ray powder diffraction (XRD) andscanning force microscopy (SFM). The DSC measurements show thesecond-order phase transition of LaAlO3 at 544 degrees C, where LaAlO3changes its symmetry from the cubic Pm3m high-temperature phase to thepseudocubic rhombohedral R(3) over barc low-temperature phase. Thisparaelastic to improper ferroelastic phase transition causes twinning inthe 51006 and 51106 planes of the pseudocubic lattice. The twinangles between the surface 51006(pseudocubic) planes of twin domainswere measured by SFM on the surface of a macroscopic (100)(cubic) cutcrystal plate. The misorientation angle omega(100) between 51006 twinsis 0.195(8)degrees, while 51106 twinning gives an angle of

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences > Crystallography and Materials Science
• Subjects: 500 Science > 550 Earth sciences and geology
• Language: English