کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1324572 977346 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The relevance of boranes and metallaboranes to the structures of p-block element nanoparticles
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
The relevance of boranes and metallaboranes to the structures of p-block element nanoparticles
چکیده انگلیسی

Recent d-block element metallaborane chemistry, in which metal identity is varied with constant ancillary ligand, demonstrates how the rising energy of the d orbitals as one moves to earlier metals gives rise to non spherical cluster shapes that permit low formal cluster electron counts. In essence, the separation of frontier orbitals from “nonbonding” orbitals required by the isolobal analogy breaks down and the resulting mixing generates additional high-lying empty orbitals concurrently with shape change. A very similar mechanism explains recent p-block cluster chemistry albeit with variation in extent of external cluster ligation as the variable and separation of external lone pair orbitals from cluster bonding as the problem. Sensible, novel explanations of the shape/electron count relationships can be discovered for large group 13 clusters by recognizing the perturbation in cluster orbital energies when stabilization by ligand interactions is removed. These observations are pertinent to an understanding of large p-block clusters with internal atoms often referred to as nanoparticles.

The electron counts of metallaboranes of the earlier transition metals can be understood if the usual isolobal requirement of three cluster nonbonding, filled metal orbitals is relaxed. Analogously, the valence counts of partially ligated main group clusters, e.g., Sn8R4, can be predicted if the requirement for localized lone pairs is relaxed.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Organometallic Chemistry - Volume 694, Issue 11, 1 May 2009, Pages 1671–1677
نویسندگان
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