8.2 Electron Sharing 269
The mechanism of the covalent bond
8.3 The H 2 Molecular Ion 270
Bonding requires a symmetric wave function
8.4 The Hydrogen Molecule 274
The spins of the electrons must be antiparallel
8.5 Complex Molecules 276
Their geometry depends on the wave functions of the outer electrons of
their atoms
8.6 Rotational Energy Levels 282
Molecular rotational spectra are in the microwave region
8.7 Vibrational Energy Levels 285
A molecule may have many different modes of vibration
8.8 Electronic Spectra of Molecules 291
How fluorescence and phsophorescence occurCHAPTER 9
Statistical Mechanics 296
9.1 Statistical Distributions 297
Three different kinds
9.2 Maxwell-Boltzmann Statistics 298
Classical particles such as gas molecules obey them
9.3 Molecular Energies in an Ideal Gas 300
They vary about an average of ^32 kT
9.4 Quantum Statistics 305
Bosons and fermions have different distribution functions
9.5 Rayleigh-Jeans Formula 311
The classical approach to blackbody radiation
9.6 Planck Radiation Law 313
How a photon gas behaves
9.7 Einstein’s Approach 318
Introducing stimulated emission
9.8 Specific Heats of Solids 320
Classical physics fails again
9.9 Free Electrons in a Metal 323
No more than one electron per quantum stateviii Contents
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