Atomic force microscopy studies of Gd-2(MoO4)(3) crystal surface

The aim of the present work was to determine what kind of data can be obtai ned from atomic force microscopy (AFM) study of ferroelastic crystals surfa ces. It is expected that surface structure of ferroelectric and ferroelasti c crystals can be correlated with the domain and:or domain boundary wall st ructures. Topography and frictional properties of freshly cleaved surfaces of ferroelastic crystal Gd-2(MoO4)(3) (GMO) were studied by combined atomic and friction force microscopy under ambient and UHV conditions. AFM images of the ab plane revealed stepped surfaces with step heights corresponding to multiplicity of the crystal lattice c constant (1.07 nm). A frictional c ontrast was observed between different domains of GMO crystal surface. We h ave found that the surface bends at the domain boundary at an angle estimat ed to be about 2.35 degrees. The twisting angle between these two planes be longing to different domains is probably due to tetragonality of the crysta l structure (a not equal b). AFM images of the be plane of GMO crystal surf ace show rough surface with linear structures along the c-axis direction. ( C) 1999 Elsevier Science Ltd. All rights reserved.