Multipole NMR. VII. Bromine NMR quadrupolar echoes in crystalline KBr

Salts with the Triborate Anion [B3O3F2(OH)2]–: A Combined Experimental and Theoretical Study

“…[11] A smaller line width (17 Hz) is observed for the signal of the 11 B nucleus of the BO 2 F 2 group, whereas the signal corresponding to the BO 2 (OH) fragments is broader (105 Hz): this finding displays the different surroundings of the boron atoms, resulting in different electric field gradients at the quadrupolar 11 B nuclei. [12] As a + 1) crystallizes in the monoclinic space group P2 1 /n (no. 14) with four formula units in the unit cell (Figure 2).…”

Effects of Higher Rank Multipoles on Relaxation of an I=3 Spin System

“…The inversion recovery spectra were obtained by averaging 64 scans, each taken with a recycling time of 1 s and delays between the inversion recovery pulses of t = 4 ms (T = 238 K), t = 3 ms (T = 243 K), and t = 2.5 ms (T = 248 K); spectra from equilibrium magnetization were acquired after a single π/2 pulse by averaging 8 scans with 1 s of recycling delay. Also in this case the zero frequency refers to the resonance of 10 B of boric acid. T = 258 K, to a lesser extent.…”

“…The experimental data have been obtained on 10 B of BSH molecules in glycerin, at different temperatures, by an inversion recovery pulse sequence and a simple 90…”

“…While the case of I = 3/2 has been explicitly solved (9,10), the cases of I = 5/2 and I = 7/2 have been dialed with the aid of numerical approximations (11). In spin systems with I = 3/2, 5/2, and 7/2, it has also been demonstrated that the effect of higher rank multipoles depends on the pulse sequence parameters and on the thermodynamic state of magnetization (6).…”

[B(CO2H)4]− and [B(CNCH3)4]3+: Homoleptic Boron Complexes Containing Carboxy and Methylisocyanide Ligands

“…[12] In Table 1 À ion (0.2 Hz) shows that quadrupole broadening is unimportant because of the small electric field gradient at the 11 B nucleus. [27][28][29] A similarly sharp signal is observed for the 11 (20 mL), and the solution was cooled to 0 8C. A mixture of NO and NO 2 , prepared from NaNO 2 (30 g, 435 mmol), H 2 SO 4 (60 mL, 1.1 mol), and water (80 mL, 4.4 mol), was added over a span of 4 h to the reaction mixture.…”