Trigonal planar molecular structure

Molecular structure (geometric structure) Linear structure Trigonal planar structure Tetrahedral structure... 

Describe the bond angles to be found in each of the following molecular structures (a) planar trigonal, (b) tetrahedral, (c) octahedral, (d) linear. 

Section 8.13 molecular structure valence shell electron-pair repulsion (VSEPR) model linear structure trigonal planar structure tetrahedral structure trigonal pyramid trigonal bipyramid octahedral structure square planar structure... 

The molecular structure of the f-butyl derivative [BpBut]ZnBul has been determined by an x-ray diffraction study, which confirms a distorted trigonal planar coordination environment for zinc, as shown by the two views in Figs. 26 and 27 (80). In comparison to tetrahedral coordination, three-coordinate zinc alkyl complexes are rare (84). 

The Lewis formula for the molecule (type AB3) predicts 3 electron groups around the central N atom. Only 1 of the two resonance structures is shown. The electronic and molecular geometries are the same, trigonal planar, because there are no lone pairs of electrons on the N atom (Section 8-6). 

The Lewis dot formula predicts 3 regions of high electron density, trigonal planar electronic geometry and angular molecular geometry around each N atom. The N atoms have sp2 hybridization (Sections 8-13 and 28-15). The three-dimensional structure is shown below. 

Boron trifluoride has a trigonal-planar structure. Formulate the bonding in terms of molecular orbitals for the Dsjj symmetry. In addition, construct wave functions for three equivalent sp2 hybrid orbitals, using the 2px, 2p, and 2s boron valence orbitals, which may be used to form three localized bonds with the three fluorines. Compare and contrast the molecular-orbital and the hybrid-orbital descriptions. 

The trigonal pyramidal molecular structure has been subjected to numerous interpretations. In Sc(btsa)3 the pyramidal ScN3 fragment was ascribed to crystal packing because the nonplanarity is lost in the gas phase [114a]. Electric dipole moment measurements confirmed a planarity in dilute benzene solutions [106a]. Zero dipole moments are also obtained for the larger lanthanide metals... 

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