Nonlinear-optical susceptibility of hilgardite-like borates ; )

Electron density in lead bromine and chlorine hilgardites on the basis of precise x‐ray diffraction data and ab‐initio calculations and correlation with the properties

“…The framework hilgardite structure and the lead polyhedrons The structures of the orthorhombic (among with some attempts to assign tetragonal symmetry [20,28]) hilgardite modifications were solved and described for different representatives of the family (Me 2 B 5 O 9 X, Me=Ca, Sr, Ba, Pb; X=Cl, Br [9,29]). All these synthetic substances, as well as the monoclinic and triclinic modifications of natural hilgardites, have polar boron-oxygen frameworks with different symmetrical combinations of B-O-layers [30].…”

“…Discovered in 2002 lead-bromine borate with the hilgardite structure, drew attention due to its high optical nonlinearity [8]. First theoretical study [9], revealed that the semi-classical approach [10] is useful to describe the Ca, Ba and Sr hilgardites, but fails in the case of elements with a nontrivial electronic structure, like Pb and Eu (see Fig.1). The conclusion is that both strongly localized electron density (like f-electrons) and delocalized (like a lonepair) can be polarized in a complex way, producing intensive high-order responses.…”

Second harmonic generation in boracites

“…At the same time, components of the second-order nonlinear susceptibility tensor, d ijk , can be calculated using the model developed in [13,14], which represents the macroscopic property of interest here as a combination of contributions from all of the chemical bonds in the crystal. This approach was shown to be applicable to borates [15,16] and hilgardite-structure haloborates [17]. The calculation procedure was described in detail in [17].…”

Crystal Growth and Associated Properties of a Nonlinear Optical Crystal—Ba2Zn(BO3)2

“…The intense research on the NLO phenomena of borates was triggered by the second-harmonic generation (SHG) reported on β-BaB 2 O 4 (β-BBO) and LiB 3 O 5 (LBO) in the late 1980s [7,8]. Thereafter, a variety of NLO borate materials have been discovered, such as BaZn 2 (BO 3 ) 2 [9], CsB 3 O 5 (CBO) [10], Ba 2 Zn(BO 3 ) 2 [11], KBe 2 BO 3 F 2 (KBBF) [12], Sr 2 Be 2 B 2 O 7 (SBBO) [13], CsLiB 6 O 10 (CLBO) [14], K 2 Al 2 B 2 O 7 (KABO) [15], BaAl 2 B 2 O 7 (BABO) [15], LiAB 4 O 7 (A = K, Rb) [16], M 2 B 5 O 9 X (M = Pb, Ca, Sr, Ba; X = Cl, Br) [17], MBi 2 B 2 O 7 (M = Ca, Sr) [18], Ca 5 (BO 3 ) 3 F [19], BiAlGa 2 (BO 3 ) 4 [20], Bi 2 ZnOB 2 O 6 [21], Ba 3 Sr 4 (BO 3 ) 3 F 5 [22], BaMBO 3 F (M = Zn, Mg) [23], M 3 B 6 O 11 F 2 (M = Sr, Ba) [24], K 3 [33], Li 4 Sr(BO 3 ) 2 [34] and K 3 Ba 3 Li 2 Al 4 B 6 O 20 F [35]. Despite these new borate-based NLO materials, β-BBO, LBO and CLBO are still the most frequently used NLO crystals in UV region, which is attributable to the difficulties of growing high quality crystals or the low transmittance in the UV region.…”