title: Dispersion forces and counterintuitive steric effects in main group molecules: heavier group 14 (Si-Pb) dichalcogenolate carbene analogues with sub-90° interligand bond angles.
abstract: The synthesis and spectroscopic and structural characterization of an extensive series of acyclic, monomeric tetrylene dichalcogenolates of formula M(ChAr)2 (M = Si, Ge, Sn, Pb; Ch = O, S, or Se; Ar = bulky m-terphenyl ligand, including two new acyclic silylenes) are described. They were found to possess several unusual features-the most notable of which is their strong tendency to display acute interligand, Ch-M-Ch, bond angles that are often well below 90°. Furthermore, and contrary to normal steric expectations, the interligand angles were found to become narrower as the size of the ligand was increased. Experimental and structural data in conjunction with high-level DFT calculations, including corrections for dispersion effects, led to the conclusion that dispersion forces play an important role in stabilizing their acute interligand angles.
authors.affiliation: Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California, 95616, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Rekken
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Brown
authors.forename: James C
authors.initials: JC
authors.lastname: Fettinger
authors.forename: Felicitas
authors.initials: F
authors.lastname: Lips
authors.forename: Heikki M
authors.initials: HM
authors.lastname: Tuononen
authors.forename: Rolfe H
authors.initials: RH
authors.lastname: Herber
authors.forename: Philip P
authors.initials: PP
authors.lastname: Power
mesh_terms: D018011:Chalcogens / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D018011:Chalcogens; D009942:Organometallic Compounds; C030011:carbene; D008697:Methane