B12Fn0/- (n=1-6) series: when do boron double chain nanoribbons become global minima?

作者：Bai, Hui; Bai, Bing; Zhang, Lin; Huang, Wei^*; Zhai, Hua-Jin^*; Li, Si-Dian^*

来源：Physical Chemistry Chemical Physics, 2017, 19(47): 31655-31665.

DOI：10.1039/c7cp05658c

• MOLECULAR-ORBITAL METHODS
• VALENCE BASIS-SETS
• PHOTOELECTRON-SPECTROSCOPY
• CLUSTERS
• PLANAR
• ANALOGS
• APPROXIMATION
• HYDROGENATION
• AROMATICITY
• TRANSITION

We present an extensive density-functional and wave function theory study of partially fluorinated B12Fn0/- (n = 1-6) series, which show that the global minima of B12Fn0/- (n = 2-6) are characterized to encompass a central boron double chain (BDC) nanoribbon and form stable BF2 groups at the corresponding BDC corner when n >= 3, but the B12F0/- system maintains the structural feature of the wellknown quasi-planar C-3v B-12. When we put the spotlight on B12F60/- species, our single-point CCSD(T) results unveil that albeit with the 3D icosahedral isomers not being their global minima, C-2 B12F6 (6.1, (1)A) and C-1 B12F6- (12.1, (2)A) as typical low-lying isomers are 0.60 and 1.95 eV more stable than their 2D planar counterparts D-3h B12F6 (6.7, (1)A') and C-2v B12F6- (12.7, (2)A(2)), respectively, alike to B12H60/- species in our previous work. Detailed bonding analyses suggest that B12Fn0/- (n = 2-5) possess ribbon aromaticity with sigma plus sigma double conjugation along the BDC nanoribbon on account of their total number of sigma and sigma delocalized electrons conforming the common electron configuration (pi(2(n+1))sigma(2n)). Furthermore, the simulated PES spectra of the global minima of B12Fn- (n = 1-6) monoanions may facilitate their experimental characterization in the foreseeable future. Our work provides new examples for ribbon aromaticity and powerful support for the F/H/Au/BO analogy.

• 出版日期2017-12-21
• 单位山西大学; 太原理工大学