Bonding VB examples 1 - VB theory VB = Valence Bond tries...

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VB theory
Bonding (VB Theory)Use the H atom orbitals, superimposed and filled using Aufbau and Pauli Principles and Hund’s Rule. VB Theory: A bond occurs when a HALF filled orbital from one atom overlaps withanother HALF filled orbital on another atom.
What if the orbitals don’t have the right geometry?What if there are not enough half-filled orbitals? Hybridization (VB Theory)
sp Hybridization (for 2 RHED)spHYBRIDIZEsp+sp
spspsp Hybridization (for 2 RHED)= position of nucelusActual orientation:Angles: 180°
sp2Hybridization (for 3 RHED)spHYBRIDIZE+p+sp2sp2sp2
sp3Hybridization (for 4 RHED)spHYBRIDIZE+p+p+sp3sp3sp3sp3
sp3sp3sp3= position of nucelusActual orientation:sp3sp3Hybridization (for 4 RHED)Angles: 109.5°
sp3d Hybridization (for 5 RHED)spHYBRIDIZE+p+p+sp3d+dsp3dsp3dsp3dsp3d
sp3d= position of nucelussp3d Hybridization (for 5 RHED)sp3dsp3dsp3dsp3dActual orientation:Angles: 90°, 120°, 180°
sp3d2Hybridization (for 6 RHED)spHYBRIDIZE+p+p+sp3d2+d+dsp3d2sp3d2sp3d2sp3d2sp3d2
= position of nucelussp3d2sp3d2sp3d2sp3d2Actual orientation:sp3d2sp3d2sp3d2Hybridization (for 6 RHED)Angles: 90°, 180°
Peripheral atomsNote that we also hybridize these.Same procedure as for the central atoms... there will be more lone pairs.
RHEDELECTRONIC GEOMETRYHYBRIDIZATION OF CENTRAL ATOM# lone pairsMOLECULAR GEOMETRYANGLES(lone pairs may distort these slightly)2linearsp0linear180°3trigonal planarsp20trigonal planar120º3trigonal planarsp21bent120°4tetrahedral sp30tetrahedral109.5° 4tetrahedral sp31trigonal pyramidal109.5° 4tetrahedral sp32bent109.5°5trigonal bipyramidalsp3d0trigonal bipyramidal90°, 180°, 120°5trigonal bipyramidalsp3d1seesaw90°, 180°, 120°5trigonal bipyramidalsp3d2T shape90°, 180°5trigonal bipyramidalsp3d3linear180°6octahedralsp3d20octahedral90°, 180°6octahedralsp3d21square pyramidal90°, 180°6octahedralsp3d22square planar90°, 180°6octahedralsp3d23T shape90°, 180°6octahedralsp3d24linear180°VSEPR AND VB FULL SUMMARYAn empty table is posted on BB to help you practice..
SIGMA BOND: formed by end to endoverlap of orbitals(all hybrids, s and p orbitals can overlap this way)ALL SINGLE BONDS ARE SIGMA BONDSPI BOND : formed by side onoverlap of two lobesof two p orbitals: notice it has TWO regionsof overlap.