Crystal structure of NdGa3[BO3]4

Crystal growth, structure, infrared spectroscopy, and luminescent properties of rare-earth gallium borates RGa3(BO3)4, R=Nd, Sm–Er, Y

“…During the last decade, also RE borates with magnetic ions (M = Cr 3+ , Fe 3+ ) attract a considerable attention, due to their interesting magnetic and magnetoelectric properties [16][17][18]. In contrast to extensive contemporary studies of aluminum, iron, and chromium borates, only a few papers are known concerning structural investigations (NdGa 3 (BO 3 ) 4 , R32 [13]), crystal growth, and spectroscopic properties [19,20] of RE gallium borates. At the same time, as was found quite recently, HoGa 3 (BO 3 ) 4 shows an unusually large magnetoelectric effect [21].…”

“…X-ray structural studies characterize huntite-like borate crystals as strictly ordered polytypes [1,[6][7][8][11][12][13]. Nevertheless, polytype structures may contain layer-packing errors.…”

Crystal Chemistry of High-Temperature Borates

“…In RM 3 (BO 3 ) 4 (M = Al, Ga, Sc, Fe, Cr) borates with the huntite-type structure, the R-oxygen polyhedra are essentially simplified and constitute trigonal prisms deformed to a different extent. In these structures, RO 6 -polyhedra are isolated from each other, and the base of the motif is formed by columns of Al, Ga, Sc, Fe, or Cr octahedra connected by isolated BO 3 -triangles [85][86][87][88][89]. When Al is substituted by Fe, and then by Ga, in the NdM 3 (BO 3 ) 4 compound, the symmetry of MO 6 -octahedron is increased, with some increase in the size of RO 6 -prisms.…”

Polytypic modifications of huntite-like rare earth aluminium and gallium boratesRM3(BO3)4, whereR= Y, Ce, Yb,M= Al, Ga

“…In the structures of both modifications three kinds of coordination polyhedra are present: trigonal prisms for RO 6 , octahedra for MO 6 , and two types of planar triangular BO 3 groups. A comparison of these structures proves their polytypic nature [1]. In each of them it is possible to distinguish two different types of layers, identical for two modifications.…”