Dynamic Light Scattering Applications of Photon Correlation Spectroscopy

In the twenty years since their inception, modern dynamic light-scattering techniques have become increasingly sophisticated, and their applications have grown exceedingly diverse. Applications of the techniques to problems in physics, chemistry, biology, medicine, and fluid mechanics have prolifer­ ated. It is probably no longer possible for one or two authors to write a monograph to cover in depth the advances in scattering techniques and the main areas in which they have made a major impact. This volume, which we expect to be the first of aseries, presents reviews of selected specialized areas by renowned experts. It makes no attempt to be comprehensive; it emphasizes a body of related applications to polymeric, biological, and colloidal systems, and to critical phenomena. The well-known monographs on dynamic light scattering by Berne and Pecora and by Chu were published almost ten years ago. They provided comprehensive treatments of the general principles of dynamic light scat­ tering and gave introductions to a wide variety of applications, but natu­ rally they could not treat the new applications and advances in older ones that have arisen in the last decade. The new applications include studies of interacting particles in solution (Chapter 4); scaling approaches to the dynamics of polymers, including polymers in semidilute solution (Chapter 5); the use of both Fabry-Perot interferometry and photon correlation spectroscopy to study bulk polymers (Chapter 6); studies of micelIes and microemulsions (Chapter 8); studies of polymer gels (Chapter 9).

1 Introduction.- References.- 2 Light Scattering Apparatus.- 2.1. Introduction.- 2.2. Electromagnetic Waves.- 2.3. Light Scattering.- 2.3.1. Background.- 2.3.2. Fluctuations.- 2.3.3. The Coherence Area.- 2.3.4. Time Dependence.- 2.3.5. Local Oscillator.- 2.4. The Light Scattering Experiment.- 2.4.1. Introduction.- 2.4.2. The Light Source.- 2.4.3. The Spectrometer.- 2.4.4. The Detector.- 2.4.5. Signal Analyzers.- 2.5. Signal-to-Noise Ratio.- 2.5.1. Introduction.- 2.5.2. Effects due to Finite Intensity.- 2.5.3. Effects due to Finite Experiment Duration.- 2.5.4. Effects due to Unwanted Scattered Light.- 2.6. Data Analysis.- 2.6.1. Introduction.- 2.6.2. Selecting the Theoretical Form.- 2.6.3. Use of the ?2Test.- 2.6.4. Summary of Possible Forms.- 2.6.5. Polydispersity.- 2.7. Special Apparatus.- 2.7.1. Electrophoretic Light Scattering.- 2.7.2. Fabry-Perot Interferometers.- 2.7.3. Software Correlators.- 2.7.4. Cross-Correlation Experiment.- 2.8. Conclusions.- References and Notes.- 3 Dynamic Depolarized Light Scattering.- 3.1. Introduction.- 3.2. Principles of Depolarized Scattering.- 3.2.1. Scattering Configurations.- 3.2.2. Physical Principles.- 3.3 Rigid Macromolecules in Dilute Solution.- 3.3.1. Hydrodynamics of Rigid Macromolecules.- 3.3.2. Interferometric Studies.- 3.3.3. Photon Correlation Studies.- 3.4. Rod-Shaped Macromolecules in Semidilute Solutions.- 3.5. Flexible Macromolecules.- 3.6. Rotation of Small Molecules in Viscous Media.- 3.7. Resonance-Enhanced Depolarized Dynamic Light.- Scattering.- References and Notes.- 4 Particle Interactions.- 4.1. Introduction.- 4.2. Quantities Measured by Light Scattering.- 4.2.1. Introduction.- 4.2.2. Monodisperse Systems.- 4.2.3. Polydisperse Systems.- 4.2.4. Discussion.- 4.3.Theory.- 4.3.1. Introduction.- 4.3.2. Stokes-Einstein Relations.- 4.3.3. The Generalized Smoluchowski Equation.- 4.3.4. Hydrodynamic Interactions.- 4.3.5. Short-Time Motions.- 4.3.6. Projection Operator Analysis.- 4.3.7. Dynamics in the Small-q Limit—Cooperative and Self-Diffusion.- 4.4. Charged Particles in Dilute Suspension (Negligible Hydrodynamic Interactions).- 4.4.1. Introduction.- 4.4.2. Single-Particle Motions.- 4.4.3. The First Cumulant.- 4.4.4. Low-g Limit and the Effect of Polydispersity.- 4.4.5. Memory Effects.- 4.5. Effects of Hydrodynamic Interactions.- 4.5.1. Introduction.- 4.5.2. Theory of the Collective Diffusion Coefficient in the Hydrodynamic Regime.- 4.5.3. Experimental Results.- 4.5.4. Microemulsions.- 4.5.5. Hydrodynamic Effects at Finite q.- 4.6. Small-Ion Effects.- 4.7. Conclusions.- 4.8. Addendum.- References and Notes.- 5 Quasielastic Light Scattering from Dilute and Semidilute Polymer Solution.- 5.1. Introduction.- 5.2.The Single Chain.- 5.2.1. Basic Polymer Statistics.- 5.2.2. Dynamical Regimes.- 5.2.3. Center-of-Mass Diffusion (q R 1).- 5.2.4. Internal Dynamics and the Dynamic Structure Factor.- 5.3. Virial Regime.- 5.4. Semidilute Solutions.- 5.4.1. Introduction.- 5.4.2. Dynamical Regimes.- 5.4.3. Conclusions.- References.- 6Dynamic Light Scattering in Bulk Polymers.- 6.1. Introduction.- 6.2. Light Scattering.- 6.3. Sources of Light Scattering.- 6.4. Theory.- 6.5. Applications.- 6.5.1. Brillouin Spectroscopy.- 6.5.2. Dynamic Central Peaks.- 6.5.3. Depolarized Rayleigh Scattering.- 6.6. Conclusions.- References.- 7 Critical Phenomena.- 7.1. Introduction.- 7.2. Critical Fluctuations.- 7.2.1. Static Critical Behavior.- 7.2.2. Dynamic Critical Behavior.- 7.3. Depolarized Rayleigh Scattering.- 7.4 .Entropy Fluctuations.- 7.4.1. Entropy Rayleigh Factor.- 7.4.2. Local Entropy Fluctuations.- 7.5. Multicomponent Fluids.- 7.5.1. Ternary Liquid Mixtures.- 7.5.2. Binary Fluid in the Presence of Isotope Exchange….- 7.5.3. Tricritical Point Behavior.- 7.6. Spinodal Decomposition and Critical Behavior Induced by Shear Flow.- 7.6.1. Spinodal Decomposition.- 7.6.2. Critical Behavior Induced by Shear Flow.- References.- 8 Laser Light Scattering in Micellar Systems.- 8.1. Introduction.- 8.2. Theoretical Aspects of Deducing Micellar Size, Polydispersity, and Shape.- 8.3. Applications of Laser Light Scattering to Micellar Systems.- 8.3.1. Aqueous Synthetic Detergent Systems.- 8.3.2. Biological Micelles.- 8.3.3. Microemulsion and Inverted Micellar Systems.- 8.4. Summary.- References.- 9Light Scattering from Polymer Gels.- 9.1. Introduction.- 9.2. Collective Modes in Gels.- 9.2.1. Collective Diffusion in a Gel.- 9.2.2. Comparison between Diffusion of Polymers and Gels.- 9.2.3. Light Scattering from Collective Diffusion Modes in aGel.- 9.2.4. Comparison between Light Scattering and Swelling of Gels.- 9.3. Kirkwood-Risemann-Type Expression of Diffusion Coefficient.- 9.3.1. Gels in Good Solvent.- 9.3.2. Light Scattering from Gels in Good Solvents.- 9.4. Phase Transition in Gels.- 9.5. Conclusion.- References.- 10 Biological Applications.- 10.1. Introduction.- 10.2. Physical Principles of Quasielastic Light Scattering.- 10.2.1. Autocorrelation Function.- 10.2.2. Power Spectrum.- 10.2.3. Translational Diffusion.- 10.2.4. Uniform Translational Motion.- 10.2.5. Rotational and Internal Motions.- 10.2.6. Number Fluctuations.- 10.2.7. Transport Coefficients and Molecular Structure.- 10.3. Instrumentation and Data Analysis.- 10.3.1. Instrumentation.- 10.3.2. Polydispersity.- 10.3.3. Concentration Effects.- 10.3.4. Charge Effects.- 10.4. Macromolecular Characterization and Interactions.- 10.4.1. Proteins.- 10.4.2. NucleicAcids.- 10.4.3. Viruses.- 10.4.4. Polysaccharides and Proteoglycans.- 10.4.5. Vesicles and Protein-Membrane Complexes.- 10.4.6. Micelles.- 10.5. Physiological and Biomedical Applications.- 10.5.1. Cataracts.- 10.5.2. Immunoassay.- 10.5.3. CellSurfaces.- 10.5.4. Monolayers, Films, and Membranes.- 10.5.5. Gels and Entangled Solutions.- 10.5.6. Muscle.- 10.5.7. Biological Velocimetry.- 10.5.8. Motility.- 10.6. Conclusion.- References.