Generation of NNBN via Photolysis of B(N₃)₃ in Low-Temperature Argon Matrices:  IR Spectra and ab Initio Calculations

Abstract

B(N3)3 was isolated in a low-temperature argon matrix and its FTIR spectrum measured. The spectrum was consistent with the known gas-phase spectrum, and splitting due to the natural abundances of 10B and 11B was observed. Upon UV photolysis, new peaks at 2100, 1861, and 1803 cm-1 assigned to the linear molecule NNBN appeared as the B(N3)3 peaks decayed. Geometry optimizations and calculations of the ground-state frequencies for 10B and 11B isotopomers B(N3)3 [MP2/6-31G(d)] and NNBN [CCSD(T)/6-311G*] are reported, and the frequencies are compared to those observed in the IR spectra. The photolytic decomposition mechanism of B(N3)3 is discussed.

Theoretical study of the decomposition mechanism of a series of group III triazides X(N3)3 (X = B, Al, Ga)

“…Furthermore, as the second step is high exothermic, the energy released from this step is enough to counteract the following barriers; therefore, once the reaction is activated, it will occur spontaneously with linear-NBNN as the main final product. These findings for the C 3h planar B(N 3 ) 3 are consistent with the previous experimental observations [15][16][17] and theoretical calculation results. [18] The unimolecular decompositions of the C 3h and C S planar Al(N 3 ) 3 both follow a two-step mechanism: (1) Al(N 3 ) 3 Figure 5c.…”

“…The decomposition product of the third step of the overall reaction is trigonal-BN 3 . However, as aforementioned, in the fourier transform infrared spectroscopy (FTIR) characterization of the photolysis products of B(N 3 ) 3 , Gilbert and coworkers [16] identified that the intermediate is not trigonal but linear NNBN molecule. We predicted that there might be isomerization between the trigonal and linear NBNN isomers.…”

“…During the process of photolytic decomposition, an intermediate trigonal BN 3 molecule was predicted to be formed first, followed by the formation of BN film. Three years later, Gilbert and coworkers studied the generation of NNBN via photolysis of B(N 3 ) 3 in low‐temperature argon matrices. Based on the ab initio calculations, they confirmed that the intermediate is not trigonal BN 3 but linear NNBN molecule.…”

Diborane(4) Azides: Surprisingly Stable Sources of Transient Iminoboranes

“…[B(N 3 ) 4 ] − is also known and is a highly energetic anion that can yield spectacularly nitrogen‐rich salts . The decomposition of binary boron azides can yield boron nitrides, which makes the general field of boron azides relevant to materials chemistry . In stark contrast to the rather well‐established chemistry of monoborane azides, there has been, to our knowledge, no explicit report on the existence of electron‐precise diborane(4) azide species.…”

Diboran(4)azide als stabile Quelle für kurzlebige Iminoborane

“…Auch [B(N 3 ) 4 ] − wurde bereits beschrieben: ein energiereiches Anion, welches eine ergiebige Quelle für hochinteressante, stickstoffreiche Salze darstellt . Die Zersetzung von binären Boraziden kann zudem als Quelle für Bornitride dienen, wodurch Borazide generell auch für Materialwissenschaften relevant werden . Im Gegensatz zu der gut erforschten Chemie der Azidomonoborane, gibt es unseres Wissens nach keine bekannten Beispiele für die Existenz von elektronenpräzisen Diboran(4)aziden.…”