| 1. |
- Matxain, Jon M, et al.
(författare)
-
New solids based on B12N12 fullerenes
- 2007
-
Ingår i: The Journal of Physical Chemistry C. - Washington, DC : American Chemical Society. - 1932-7447 .- 1932-7455. ; 111:36, s. 13354-60
-
Tidskriftsartikel (refereegranskat)abstract
- In recent years, BN fullerenes have been synthesized experimentally. As their carbon counterparts, these BN fullerenes could be assembled in molecular solids, but this possibility has been studied little in the literature. In this work, we focus on the smallest synthesized BN fullerene, B12N12, which is built by squares and hexagons. First, the interaction between two of these fullerenes has been analyzed, using the hybrid B3LYP and MPW1PW91 density functional methods. Two different interactions have been studied in the dimer, a square facing a square (S−S) and a hexagon facing a hexagon (H−H). In both cases, a B is facing a N. The most stable dimer was found to be S−S facing, with covalent interactions between the monomers, but other dimers with weak interactions have been found as well, which opens possibilities of new systems, as in the case of fullerene dimers and solids. The solids resulting from the infinite repetition of the characterized dimers were optimized, finding two different solids, with covalent and weak interactions between monomers, respectively. The solid with covalent interactions is a nanoporous material that is more stable by around 12 eV. Because of the nanoporous character of this solid, it could be used for heterogeneous catalysis, molecular transport, and so forth. The SIESTA code with the GGA-PBE density functional method has been used for the solid-state calculations.
|
|
| 2. |
- Matxain, Jon M., et al.
(författare)
-
Endohedral (X@ZniSi)i=4-160,± Nanoclusters, X = Li, Na, K, Cl, Br
- 2007
-
Ingår i: The Journal of Physical Chemistry C. - Washington, DC : American Chemical Society. - 1932-7447 .- 1932-7455. ; 111:9, s. 3560-3565
-
Tidskriftsartikel (refereegranskat)abstract
- Endohedral (X@ZniSi)q structures have been characterized, with X being alkali metals such as Li, Na, and K or halogens such as Cl and Br, 4 > i > 16, and q = -1, 0, 1. In these structures, the atoms are trapped inside previously characterized spheroid hollow structures with positively charged Zn atoms and negatively charged S atoms. Moreover, although the radii of all atoms are similar, Zn atoms are located more inside the structure. The alkali metals are found to be trapped inside a larger number of spheroid structures than the halogens. The parameters determining the stability of the endohedral structures are the charge and size of the trapped atom, along with the sphericity of the cluster.
|
|
