Antibonding molecular orbital

Chapter 15 ? 2010, Prentice Hall Organic Chemistry, 7th Edition L. G. Wade, Jr. Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy Chaper 15 * Conjugated Systems Conjugated double bonds are separated by one single bond. Isolated double bonds are separated by two or more single bonds. Conjugated double bonds are more stable than isolated ones. Chaper 15 Chaper 15 * Heat of Hydrogenation of Conjugated Bonds For conjugated double bonds, the heat of hydrogenation is less than the sum for the individual double bonds. The more stable the compound, the less heat released during hydrogenation, Conjugated double bonds have extra stability. Chaper 15 Chaper 15 * Relative Stabilities twice 1-pentene more substituted Chaper 15 Chaper 15 * Structure of 1,3-Butadiene

Chapter 2 ? 2010, Prentice Hall Organic Chemistry, 7th Edition L. G. Wade, Jr. Structure and Properties of Organic Molecules Chapter 2 * Wave Properties of Electrons Standing wave vibrates in fixed location. Wave function, ?, is a mathematical description of size, shape, and orientation. Amplitude may be positive or negative. Node: Amplitude is zero. Chapter 2 Chapter 2 * Wave Interactions Linear combination of atomic orbitals: between different atoms is bond formation. on the same atom is hybridization. Conservation of orbitals Waves that are in phase add together. Amplitude increases. Waves that are out of phase cancel out. Chapter 2 Chapter 2 * Sigma Bonding Electron density lies between the nuclei. A bond may be formed by s?s, p?p, s?p, or hybridized orbital overlaps.