Syntheses, band structures and optical properties of Zn3B2O6 and KZn4B3O9

Syntheses and crystal structures of the α- and β-forms of zinc orthoborate, Zn3B2O6

“…Subsequently, Baur and Tillmanns [7] pointed out that the structure could be refined in the centric group I2/c to essentially the same R value (0.133), and more recently, Chen et al reported a structural refinement in a standard group C2/c with an R factor of 0.053 [8]. The present X-ray structure analysis has fully confirmed their results and our data are more accurate due to the use of a larger reflection number/parameter number ratio (>17).…”

“…In the binary system of ZnO-B 2 O 3 , at least three compounds have been proposed including ZnB 4 O 7 [4], Zn 3 B 2 O 6 [5], and Zn 4 O(BO 2 ) 6 [6]. The crystal structure of Zn 3 B 2 O 6 (which we call the hightemperature ␤-form of Zn 3 B 2 O 6 here) was first determined by Garcia-blanco and Fayos to be in a noncentrosymmetric group Ic [5], subsequently corrected by Baur and Tillmanns in a centrosymmetric group I2/c [7], and recently further refined by Chen et al in a standard group C2/c [8]. However, the existence of high-temperature and low-temperature polymorphs for Zn 3 B 2 O 6 has not been known so far.…”

Processing and photoluminescence properties of surface crystallized ZnO glass-ceramics

“…Since ZnO works as intermediate (ZnO 2 : bond dissociation energy 301 kJ/mol) or network modifier (ZnO 4 : bond dissociation energy 151 kJ/mol) [11], it is suggested that additional Al 2 O 3 , which can work as a network former, affects coordination state of ZnO into a network modifier. Note that Zinc takes 4-coordination state in precipitated crystallites, such as KZn 4 B 3 O 9 [12], α-Zn 3 B 2 O 6 [13], or ZnO.…”

Fabrication of surface crystallized glasses with α-Zn3B2O6 and their optical property

“…Since α-Zn 3 B 2 O 6 always shows surface crystallization, it is suggested that network modifier CaO affects surface structure of glass suitable for nucleation of α-Zn 3 B 2 O 6 precipitation. Although both CaO and K 2 O belong to network modifier group, the former induced precipitation of α-Zn 3 B 2 O 6 whereas the latter induced KZn 4 B 3 O 9 [15]. It is suggested that α-Zn 3 B 2 O 6 was crystallized from the CaO-ZnO-B 2 O 3 glass because of lack of Ca x Zn y B z O (x + y;1.5z) ternary crystalline system whereas ternary KZn 4 B 3 O 9 can be crystallized in K 2 O-ZnO-B 2 O 3 glass system.…”