GOAL: a quantitative interpretation of the vibrational spectra

Slides:



Advertisements
Similar presentations
WHAT IS ENERGY? ABILITY TO DO WORK MEASURED IN JOULES (J)
Advertisements

Atomic Vibrations in Solids: phonons
METO 621 Lesson 6. Absorption by gaseous species Particles in the atmosphere are absorbers of radiation. Absorption is inherently a quantum process. A.
Most lasers are made of some material such as a crystal of ruby or a gas that is enclosed in a glass tube, like argon. Suppose an atom was in an excited.
Small Coupled Oscillations. Types of motion Each multi-particle body has different types of degrees of freedom: translational, rotational and oscillatory.
NORMAL COORDINATE ANALYSIS OF XY2 BENT MOLECULE – PART 3
Computational Chemistry
Chemistry 2 Lecture 10 Vibronic Spectroscopy. Learning outcomes from lecture 9 Excitations in the visible and ultraviolet correspond to excitations of.
DFT STUDY OF SOLVENT EFFECTS ON CONFORMATIONAL EQUILIBRIA AND
Case Studies Class 5. Computational Chemistry Structure of molecules and their reactivities Two major areas –molecular mechanics –electronic structure.
Lecture 3 – 4. October 2010 Molecular force field 1.
The spectral method: time-dependent quantum dynamics of FHF - : Potential Energy Surface, Vibrational Eigenfunctions and Infrared Spectrum. Guillermo Pérez.
Theoretical and computationalphysical chemistry group Theoretical characterization of  -helix and  -hairpin folding kinetics Theoretical characterization.
Chemistry 6440 / 7440 Vibrational Frequency Calculations.
Jaguar in the Real World Used in national labs, industrial companies, and academic institutions worldwide Application areas include pharmaceutical, chemical,
Vibrations of polyatomic molecules
Frequency Calculation. *A nonlinear molecule with n atoms has 3n — 6 normal modes: the motion of each atom can be described by 3 vectors, along the x,
Vibrational Spectroscopy HH O Bend. Diatomic Molecules So far we have studied vibrational spectroscopy in the form of harmonic and anharmonic oscillators.
Control Systems and Adaptive Process. Design, and control methods and strategies 1.
Vibrations. Near Equilibrium  Select generalized coordinates Kinetic energy is a homogeneous quadratic function of generalized velocityKinetic energy.
Introduction to Infrared Spectroscopy
 PART Requirements for Spectroscopic Techniques for Polymers 1. High resolution 2. High sensitivity (>1%) 3. High selectivity between molecular.
Vibrational Spectroscopy
Objectives of this course
Geometry Optimisation Modelling OH + C 2 H 4 *CH 2 -CH 2 -OH CH 3 -CH 2 -O* 3D PES.
Infrared Spectroscopy
Which method? We’re using Density Functional Theory (DFT) as it gives us the most accurate results for transition metals in the least amount of time.
Dec YUNWEN TAO CATCO Group Department of Chemistry Southern Methodist University Local Vibrational Modes: The Unique Corresponding Equivalent of.
Matlab tools for controlling low-level image properties
Ab Initio and DFT Calculations for the Vibrational Frequencies and Barrier to Planarity of Cyclopentene and its Deuterated Isotopomers Abdulaziz Al-Saadi.
Praveenkumar Boopalachandran, 1 Jaan Laane 1 and Norman C. Craig 2 1 Department of Chemistry, Texas A&M University, College Station, Texas Department.
Hanjo Lim School of Electrical & Computer Engineering Lecture 2. Basic Theory of PhCs : EM waves in mixed dielectric.
Physical Chemistry 2 nd Edition Thomas Engel, Philip Reid Chapter 18 A Quantum Mechanical Model for the Vibration and Rotation of Molecules.
Vibrational, Electronic, and Fluorescence Spectra and Ab Initio Calculations of 1,4-Benzodioxan (14BZD) Juan Yang, Martin Wagner, Daniel Autrey, and Jaan.
Modal Theory of Multiple Degree of Freedom System Dept. of Mechanical Engineering Yungpeng Wang 南臺科技大學 STUST.
A Practical Procedure for ab initio Determination of Vibrational Spectroscopic Constants, Resonances, and Polyads William F. Polik Hope College, Holland,
FTIR Gas Analysis Module Spectrum GX FTIR System – Perkin Elmer – Volume: 8.5 L – Wavenumber range: 10, cm -1 – Resolution: cm -1 M-5-22-V.
HEAT TRANSFER FINITE ELEMENT FORMULATION
Frequency Calculations Lecture CompChem 3 Chemistry 347 Hope College.
Lecture 13. Geometry Optimization References Computational chemistry: Introduction to the theory and applications of molecular and quantum mechanics, E.
Claudia Ambrosch-Draxl Institute for Theoretical Physics University Graz Forces and Phonons within WIEN2k.
Solving Vibrational Problems… So easy!! …right? How to model the potential? 9x9 matrix. Don’t screw up your partials!
Developing a Force Field Molecular Mechanics. Experimental One Dimensional PES Quantum mechanics tells us that vibrational energy levels are quantized,
Vibrations of Multi Degree of Freedom Systems A Two Degree of Freedom System: Equation of Motion:
Lecture 8. Chemical Bonding
Tao Peng and Robert J. Le Roy
Schrödinger Equation – Model Systems: We have carefully considered the development of the Schrödinger equation for important model systems – the one, two.
0 Jack SimonsJack Simons, Henry Eyring Scientist and Professor Chemistry Department University of Utah Electronic Structure Theory Session 12.
Course 1: Introduction Warren J. Hehre, A Guide to Molecular Mechanics and Quantum Chemical Calculations, Wavefunction, Inc Von Karman Ave., Suite.
FAR-IR ACTION SPECTROSCOPY OF AMINOPHENOL AND ETHYLVANILLIN: EXPERIMENT AND THEORY Vasyl Yatsyna, Daniël Bakker*, Raimund Feifel, Vitali Zhaunerchyk, Anouk.
MOLECULAR SPECTROSCOPY
These are at 326 cm -1 and 620 cm -1 which are respectively assigned to the ν(C1N1N2) and imidazole ring deformation mode. The phenyl ring breathing mode.
BREAKING THE SYMMETRY IN JAHN-TELLER ACTIVE MOLECULES
Computational Chemistry:
OSE801 Engineering System Identification Spring 2010
IR and Raman spectra of N2H2
MANE 4240 & CIVL 4240 Introduction to Finite Elements
Production of an S(α,β) Covariance Matrix with a Monte Carlo-Generated
Vibrational spectral investigations of Glyoxime
International Symposium on Molecular Spectroscopy
Chapter 9: Spectroscopic Identification of Organic Compounds
Analytical methods Prepared By Dr. Biswajit Saha.
Evaluating transition matrix elements using character tables
Problem 1: m x(t) f(t) c k m,R c k m Figure 1 Kinetic energy: Idisc θ
m1 VIBRATIONAL THEORY p.55 bonds ~ springs E = ½ kx2 m2 x is + or -
AAE 556 Aeroelasticity Lecture 24
Computation of Harmonic and Anharmonic Vibrational Spectra
Introduction During the last years the use of Fourier Transform Infrared spectroscopy (FTIR) to determine the structure of biological macromolecules.
Simple case: a diatomic with masses m1 and m2
Vibrational Spectroscopy
Presentation transcript:

GOAL: a quantitative interpretation of the vibrational spectra The amount of information we can obtain from a vibrational spectrum depends on our ability to translate spectroscopic observables (frequency and intensity) in terms of molecular architecture GOAL: a quantitative interpretation of the vibrational spectra (IR and Raman) i.e. the assignment of the whole spectrum to the respective normal modes of vibration: INTERPRETATION STRATEGY THEORETICAL APPROACH NORMAL COORDINATE ANALYSIS (Wilson GF method): Input: 1. Geometry (G matrix) 2. Energetics (Force constants, F matrix) Secular equation: Output: 1. Eigenvalues (frequencies) 2. Eigenvectors (nuclear displacements) 3. IR Intensities COMPUTATIONAL METHODS: 1. MOLECULAR MECHANICS (to explore the potential energy surface) 2. DENSITY FUNCTIONAL THEORY, DFT (to refine geometry parameters and to evaluate the energetics (Force Constants)

Polistirene sindiotattico forma a (zig-zag planare)

Risultati dell’analisi vibrazionale

Polistirene sindiotattico forme g, d, e (elica s(2/1)2

Conformational Search (Molecular Mechanics) force field MM+ Un polimero amorfo Unsaturated polyester (propylene glycol / maleic anhydride) Diethylfumarate (DEF)

DFT  : Raman  : IR NCA