Static Light Scattering. Outline of Static Light Scattering FMeasurement system FRayleigh scattering FStatic structure factor FForm factors FPractical.

Slides:

Advertisements

Similar presentations

Viscosity of Dilute Polymer Solutions

Advertisements

Light interaction with matter Wavelength ~ 500nm When light interacts with systems of much larger sizes (few cm, m): Geometric optics When light interacts.

Introduction to Light Scattering A bulk analytical technique

Seminar PCF “Lightscattering”. 1. Light Scattering – Theoretical Background 1.1. Introduction Light-wave interacts with the charges constituting a given.

Electromagnetic Radiation Cont…. Lecture 3. Dispersion of Radiation If we look carefully at the equation n i = c/v i and remember that the speed of radiation.

Light Waves and Polarization Xavier Fernando Ryerson Communications Lab

Lecture 17. Light Scattering/Viscometry. What is light scattering? In the lab…

1 Outline Basic Idea Simple Theory Design Points Calibration of Forces Selected Biological Applications.

BIOP – Center for Biomedical Optics and New Laser Systems Light scattering from a single particle Peter E. Andersen Optics and Fluid Dynamics Dept. Risø.

Wavelike Properties of Electromagnetic Radiation 1.Wave parameters 2.Refraction a.Index of refraction Snell’s Law b. Prism monochrometers 3.Diffraction.

Light Scattering Topic 3 Part 2 Biophysics. Single Particle Rough Treatment Sample - dipole Light Source k 0  The scattering angle, , is defined w/r.

The Propagation of Light

The use of light scattering in characterizing lignin.

Ultraviolet and Visible Spectroscopy Chemical Ideas 6.8.

Lecture : 2 Light scattering and determination of the size of macromolecules.

Nanoparticle Optics Lab Part II Light Scattering.

Resonances and optical constants of dielectrics: basic light-matter interaction.

Lecture 8: Measurement of Nanoscale forces II. What did we cover in the last lecture? The spring constant of an AFM cantilever is determined by its material.

Chapter 22: Electromagnetic Waves

Rayleigh’s Scattering

March 4, 2011 Turn in HW 5; Pick up HW 6 Today: Finish R&L Chapter 3 Next: Special Relativity.

Nanoparticles Characterization: Measurement of the particles size by the PCS technique MSc. Priscyla D. Marcato Dr. Nelson Durán.

Introduction to radiative transfer

Introduction to PHOTON CORRELATION SPECTROSCOPY

METO 621 Lesson 5. Natural broadening The line width (full width at half maximum) of the Lorentz profile is the damping parameter, . For an isolated.

Advanced GPC Part 2 – GPC and Light Scattering

The birth of quantum mechanics Until nearly the close of the 19 th century, classical mechanics and classical electrodynamics had been largely successful.

PHY 102: Waves & Quanta Topic 8 Diffraction II John Cockburn Room E15)

Osmosis and Colloids. Osmotic Pressure  Another colligative property  A solution and a pure solvent are separated by a semipermeable membrane - membrane.

Modern Optics Lab Lab 5 Part 1: Experiments involving Light Polarization  Measuring light transmission through a dichroic material (“polarizer sheet”)

1 Stephen SchultzFiber Optics Fall Optical Fibers.

UGC-DAE Consortium for Scientific Research, Mumbai Light Scattering studies on Colloids & Gels Goutam Ghosh.

Unit 2, Part 3: Characterizing Nanostructure Size Dr. Brian Grady-Lecturer

Chapter 26 - RADIUS OF GYRATION CALCULATIONS

Rayleigh Scattering & Mie Scattering

Polarization Polarization is a characteristic of all transverse waves.

Rayleigh and Mie Scattering

Static & Dynamic Light Scattering First quantitative experiments in 1869 by Tyndall (scattering of small particles in the air – Tyndall effect) 1871 –

Attenuation by absorption and scattering

Wenbo Sun, Bruce Wielicki, David Young, and Constantine Lukashin 1.Introduction 2.Objective 3.Effect of anisotropic air molecules on radiation polarization.

Scattering by particles

Real part of refractive index ( m r ): How matter slows down the light: where c is speed of light Question 3: Into which direction does the Scattered radiation.

Ch 24 pages Lecture 9 – Flexible macromolecules.

FIG. 5.1 Multiple scattering is viewed as a random walk of the photon in diffusing wave spectroscopy (DWS)

ORE 654 Applications of Ocean Acoustics Lecture 6c Scattering 1 Bruce Howe Ocean and Resources Engineering School of Ocean and Earth Science and Technology.

Lecture/Lab: Interaction of light with particles. Mie’s solution.

1 UV-Vis Absorption Spectroscopy Lecture Measurement of Transmittance and Absorbance: The power of the beam transmitted by the analyte solution.

1 PHY Lecture 5 Interaction of solar radiation and the atmosphere.

Light Scattering (pp in Shaw and pp in Hiemenz and Rajagopalan) Introduction Rayleigh Scattering Debye Scattering, Zimm Plots Dynamic.

Is Matter Around Us Pure Solutions Solution A solution is a homogeneous mixture of two or more components. The dissolving agent is the solvent. The substance.

Rayleigh Scattering Outline

Ch 10 Pages ; Lecture 24 – Introduction to Spectroscopy.

Electromagnetism Around 1800 classical physics knew: - 1/r 2 Force law of attraction between positive & negative charges. - v ×B Force law for a moving.

Kinetic Properties (see Chapter 2 in Shaw, pp ) Sedimentation and Creaming: Stokes’ Law Brownian Motion and Diffusion Osmotic Pressure Next lecture:

Bremsstrahlung of fast electron on graphene

Sunlight. Question: When you look up at the sky during the day, is the light from distant stars reaching your eyes?

Introduction to Polymer Physics

Chemistry 367L/392N Macromolecular Chemistry Lecture 10.

The Interaction of Light and Matter: a and n

Light Scattering Biophysics

Static Light Scattering Part 2: Solute characteristics

Chapter 25 Wave Optics.

Suspended Nanomaterials

NEPHELOMETRY AND TURBIDIMETRY

Light scattering method Introduction: The illumination of dust particles is an illustration of light scattering, not of reflection. Reflection is the deviation.

Analytical Ultracentrifugation

General theory of scattering in isotropic media

Light Scattering Biophysics

Polarization via Rayleigh Scattering

Presentation transcript:

Static Light Scattering

Outline of Static Light Scattering FMeasurement system FRayleigh scattering FStatic structure factor FForm factors FPractical problems

Light Scattering Measurement System

Scattering Wavevector top view scattering wavevector wavevector

Lengths Probed by Light Scattering Light scattering probes the length of ~1/k. ~ 33 nm ~ 100 nm

Scattering Volume depends on the focusing of the laser. specified by the two pinholes. The scattering volume is an open system.

Rayleigh Scattering by a Small Particle Why is the sky blue? Why is the sunset reddish? Polarization in the particle changes in phase with the incoming light. The particle is now a broad- casting station, emanating radiation in all directions.

Rayleigh Scattering Rayleigh scattering by a particle in vacuum  : polarizability of the particle  particle volume I maximizes at  ´ = 90°. Usually, LS is detected in the horizontal plane.

Scattering by a Chain Molecule (in Vacuum) The beams scattered by the two particles interfere. Two parts of a large molecule interfere more or less constructively. Therefore, a large molecule scatters the light more strongly than many small particles do.

Static Structure Factors suspension of small particles single large molecule many large molecules

Structure Factor of a Polymer Chain low-angle scattering RgRg radius of gyration high-angle scattering

Form Factors Angular dependence of P(k) allows us to determine the shape of the molecule.

Form Factor of a Sphere Rayleigh-Gans formula EXCEL problems 1. Plot P as a function of kR. 2. Plot P as a function of  for R = 10, 30, 100, 300, and 1000 nm. Assume specific values of n and.

Light Scattering of a Solution The formula derived for a molecule in vacuum can be used just by replacing  with  ex. A more convenient expression

Light Scattering of Polymer Solutions Measure I(k) for pure solvent. Measure I(k) for solutions of a given polymer at different concentrations. Calculate I ex (k).

Zimm Plot

Example of Zimm Plot Polyguanidine in THF

Differential Refractive Index At low concentrations, Often, we can approximate dn/dc as

Concentration Effect on Scattering Intensity scattering at low concentrations

Scattering by a Suspension of Spheres mass/volume At constant c, At constant , number/volume

Scattering by Spheres at Constant c EXCEL problems Plot R 3 P(kR) as a function of  for R = 10, 30, 100, 300, and 1000 nm. Assume specific values of n and. At constant c,

Scattering by Spheres at Constant  At constant , EXCEL problems Plot R 6 P(kR) as a function of  for R = 10, 30, 100, 300, and 1000 nm. Assume specific values of n and.

Changes in the Scattering Intensity Spheres aggregate into larger spheres: Porous spheres become nonporous without changing R: ( n porous spheres form 1 nonporous sphere) Nonporous spheres become porous without changing the mass: