Li₄Ba[BN₂]₂ – Structure and Vibrational Spectra

Sr6(BO3)3BN2: An Oxido–Nitrido–Borate Phosphor Featuring BN2 Dumbbells

“…23−26 Moreover, we present first spectroscopic results on the title compound and thermal analyses to assess the suitability of these compounds to act as host structures for sensitized phosphors. 27,29 The local surrounding of both BN 2 3− anions in Sr 6 (BO 3 ) 3 BN 2 is depicted in Figure 2b; it shows that the local surrounding of B3N 2 is very similar to that found in LiMg[BN 2 ] also crystallizing in a tetragonal space group and comprising linear BN 2 dumbbells, 30 in contrast to some others where bent anions were described. Figure 2a displays the arrangement of the BN 2 3− anions in the channel; the B−B distances of 3.51 Å are well beyond covalent interactions.…”

“…For instance, in Gd 4 (BO 2 )­O 5 F, a B–O bond length of 1.213(1) Å was found . Bonds within the more frequent respective nitride species are somewhat longer, in the regime of those in Li 4 Ba­[BN 2 ] 2 (1.34 Å) or MBa 8 [BN 2 ] 6 (M = Sr, Eu) (1.32 and 1.36 Å) . Recently, Pöttgen et al discussed the coordination polyhedra around BN 2 3– anions of several compounds in comparison to Li 4 Ba­[BN 2 ] 2 . , The local surrounding of both BN 2 3– anions in Sr 6 (BO 3 ) 3 BN 2 is depicted in Figure b; it shows that the local surrounding of B3N 2 is very similar to that found in LiMg­[BN 2 ] also crystallizing in a tetragonal space group and comprising linear BN 2 dumbbells, in contrast to some others where bent anions were described.…”

“…The band positions and the respective assignment are summarized in Table . The IR spectrum comprises mainly the asymmetric stretching vibrations of the BO 3 units in the range 1350–1000 cm –1 and the deformation vibrations thereof in the region 820–550 cm –1 . , The strongest peaks in the Raman spectrum belong to the symmetric stretching vibration of BO 3 at 914 cm –1 and the ν s (BN 2 ) vibration at 1071 cm –1 which is characteristic for linear BN 2 units. ,, The band at 1365 cm –1 in the Raman spectrum stems from BN, which sticks to the surface of the Sr 6 (BO 3 ) 3 BN 2 crystal and which we were not able to remove completely. BN was used as starting material in the synthesis which yielded the single crystals but not a phase pure sample.…”

“…49,50 The strongest peaks in the Raman spectrum belong to the symmetric stretching vibration of BO 3 at 914 cm −1 and the ν s (BN 2 ) vibration at 1071 cm −1 which is characteristic for linear BN 2 units. 27,32,35 The band at 1365 cm −1 in the Raman spectrum stems from BN, which sticks to the surface of the Sr 6 (BO 3 ) 3 BN 2 crystal and which we were not able to remove completely. BN was used as starting material in the synthesis which yielded the single crystals but not a phase pure sample.…”

The First Alkaline‐Earth Azidoaurate(III), Ba[Au(N3)4]2 ⋅ 4 H2O

“…[17][18] The comparison of the wavenumbers of stretching modes for the outermost (N�N) and the inner (NÀ N) bonds shows a slight but significant shift to higher wavenumbers in favor of the Ba compound. These observation are in good accordance with previous reports [37,38] and can be explained by reduction of partial negative charge on the [Au(N 3 ) 4 ] À groups by the positive counterions which in turn will give rise to an increase of the (NÀ N) frequencies and force constants (counterion effect). The effect is more pronounced in presence of strong electropositive small cations with high positive charges.…”