Abstract
Ab initio calculations at MP2/6-31G*, B3LYP/6-31G*, and B3LYP/6-311+G** levels indicate relatively high potential barriers for the intramolecular rearrangement of B9H92- via the single DSD (diamond−square−diamond) or the double DSD mechanism, 28.4 and 21.3 kcal/mol, respectively. However, its open face-protonated form, B9H10- (2b) is highly fluctional. Two other minima, 2a (C2v) and 2c (C3v) have energies 1.1 and 9.7 kcal/mol higher than 2b. Facile rotation of the BH2 group in 2a is coupled with reversible opening of the boron cage from the closo to a nido form. Structure 2c, with a face-bound proton, is a very shallow minimum along the degenerate rearrangement pathway of 2b. None of the optimized structures of B9H10- give calculated 11B chemical shifts corresponding to experiment; the NMR assignments and interpretation need to be refined. Members of the BnHn+1- series (n = 6−8, 10, and 12) have both common as well as specific features. All BnHn+1- species are fluxional, due to rapid proton migration. The...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
