The fascinating story of boron–boron triple bond
نویسنده
چکیده
CURRENT SCIENCE, VOL. 104, NO. 12, 25 JUNE 2013 1601 The new international standards are expected to help genebanks worldwide to conserve crop diversity in a more efficient and cost-effective manner. They provide a basis for establishing the norms and standards essential for the smooth operation of a genebank. They can be used by genebank curators as a source of guidance for developing standard operating procedures. They would also be helpful for developing quality management systems in genebanks. A systematic application of these standards will, however, require strong national, regional and global commitment and continuous financial support for capacity development and upgrading professional skills. After approval of the CGRFA, the Genebank Standards for Plant Genetic Resources for Food and Agriculture is expected to be published by the FAO and widely disseminated amongst decisionmakers and relevant stakeholders. All genebanks are expected to adopt these standards, as far as possible, to ensure conservation of genetic resources under optimal conditions, for perpetuity. It is further expected that species-specific standards be developed in future for further fine-tuning of this endeavour.
منابع مشابه
Spying on the boron-boron triple bond using spin-spin coupling measured from 11B solid-state NMR spectroscopy.
There is currently tremendous interest in the previously documented example of a stable species exhibiting a boron-boron triple bond (Science, 2012, 336, 1420). Notably, it has recently been stated using arguments based on force constants that this diboryne may not, in reality, feature a boron-boron triple bond. Here, we use advanced solid-state NMR and computational methodology in order to dir...
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متن کاملThe boron–boron triple bond in NHC→B 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 B←NHC† †This paper is dedicated to Professor Peter Paetzold on the occasion of his 80th birthday. ‡ ‡Electronic supplementary information (ESI) available: Details of the theoretical calculations and coordinates and energies of the calculated molecules. See DOI: 10.1039/c5sc01504a
Quantum chemical calculations of the compound B2(NHC )2 and a thorough examination of the electronic structure with an energy decomposition analysis provide strong evidence for the appearance of boron–boron triple bond character. This holds for the model compound and for the isolated diboryne B2(NHC )2 of Braunschweig which has an even slightly shorter B–B bond. The bonding situation in the mol...
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