Linked Life Data

15046507

Source:http://linkedlifedata.com/resource/pubmed/id/15046507

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-3-29
pubmed:abstractText
The aim of this paper was to investigate why the geometries of nonmetal hydrides are often not in accordance with the VSEPR model. From a consideration of interligand distances in a variety of BX(4), CX(4), and NX(4) molecules where X is a ligand or a lone pair and in which there are at least two H ligands we have shown that the hydrogen ligands are essentially close-packed. For each of the central atoms we have obtained a value for the ligand radius of hydrogen. These radii decrease with decreasing negative charge and increasing positive charge of the hydrogen ligand as the electronegativity of the central atom increases, as has been found previously for other ligands such as F and Cl. We show that ligand-ligand intractions are an important factor in determining bond angles in hydrides and that the ligand close-packing (LCP) model gives a better explanation of bond angles than the VSEPR model according to which bond angles depend on the electronegativity of the ligand rather than on its size. For example, although the very small angles in PH(3) and SH(2) are not in accord with the VSEPR model, they are consistent with the LCP model in that they are a consequence of the small size of hydrogen ligands which are pushed together by the lone pairs until they are almost close-packed.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Apr
pubmed:issn
0020-1669
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2318-23
pubmed:year
2004
pubmed:articleTitle
The geometry of nonmetal hydrides and the ligand radius of hydrogen.
pubmed:affiliation
Department of Chemistry, McMaster University, Hamilton, Ontario, L8S 4M1 Canada.
pubmed:publicationType
Journal Article