Electronic
Page 1: Introduction
Electronic Spectroscopy: Presentation by Teo Yin Yin, PhD.
Contact Information:
Room: L7-25, Bangunan Makmal Kimia
Tel: 03-7967 7022 Ext 2546
Email: yinyinteo@um.edu.my
Page 2: Wave Function
General Form of Wavefunction: A combination of radial and angular parts.
Wavefunction Representation: Complex notations utilized, involving angular functions and radial functions:
$\Psi_{n,l,m}(R,r,\theta,\phi) = R(r)P(\theta) e^{im\phi}$
Parameters include quantum numbers related to angular momentum.
Page 3: Quantum Numbers
Four Quantum Numbers: Required to describe atoms:
n: Principal quantum number.
l: Azimuthal quantum number (orbital type).
m: Magnetic quantum number (orientation of the orbital).
s: Spin quantum number.
Atomic Orbital: A one-electron wavefunction; an electron described by a specific wavefunction resides in that orbital.
Example: An electron in state $|\psi_{1,0,0}\rangle$ occupies orbital (n=1, l=0, m=0).
Page 4: Quantum Number Functions
Quantum Number Explained:
Principal (n): Values 1, 2, 3,…; influences energy and size of the orbital.
Orbital (l): Values from 0 to n-1; dictates the shape of the orbital.
Spin (s): Values of ±1/2; describes the spin of the electron.
Spin Orientations: Each electron's spin can only take certain values relative to the z-axis.
Page 5: Hydrogen Atom Spectrum
Hydrogen Atom Energy Contributions:
Attraction between the electron and nucleus.
Repulsion between electrons, which is absent in hydrogen.
Orbital Energy: In hydrogen, all orbitals with the same n value have the same energy due to the lack of inter-electronic interactions.
Page 6: Rydberg Constant and Orbital Energies
Rydberg Constant: $R_H = 109,677 ext{ cm}^{-1}$.
Orbital Energy Calculation:
Given by: $E_n = -\frac{R_H Z^2}{n^2}$ where:
$Z$: Atomic number, $n$: Principal quantum number.
Page 7: Energy Levels in Hydrogen Atom
Ionization Energy (I): Represents the minimum energy needed to remove an electron from the hydrogen atom to n = ∞.
Ionization Energy Value: For hydrogen, $I = 13.6 ext{ eV}$.
Page 8: Ground State Energy
Ground State Energy: Lowest energy state for hydrogen is $E = -hcR_H$ corresponding to n = 1.
Ionization Point: Occurs at $n = ∞$, when energy is supplied.
Page 9: Hydrogenic Atoms
Definition of Hydrogenic Atom: A one-electron atom or ion with atomic number Z (examples: H, He+, Li2+, etc.).
Emission Spectrum: Electron transitions create distinct lines in a spectrum observed when hydrogen is ionized and excited.
Page 10: Selection Rules for Transitions
Selection Rules:
Allowable transitions: $ \Delta n = ext{any}, \Delta l = \pm1$
Energy Levels Series: Transitions generate series like Lyman (n=1), Balmer (n=2), etc.
Spectral Line Emission: Occurs when an electron transitions from higher to lower energy state.
Page 11: Atomic Hydrogen Spectrum
Hydrogen Spectrum: Shows different regions; UV (for n=2), visible (for n=3), and IR ranges for different transitions.
Page 12: Emission Spectrum and Splitting
Fine Structure: Energy level splitting due to spin-orbit coupling, affecting emission spectra.
Page 13: Spectroscopic Terms
Microstates: Different configurations of electron arrangements fulfilling the electronic designation.
Electronic Designation: Symbolized by principal quantum and sub-level information (e.g., 2p²).
Page 14: Microstates Variability
Microstate Energy Variation: Influenced by inter-electronic repulsion; terms are groups of microstates with the same energy.
Page 15: Term Symbols
Term Symbol Representation:
Mentioned representations include S, P, D, F letters denoting total angular momentum.
Page 16: Relation Between Spin and Angular Momentum
Spin and Magnetic Moments: Each electron contributes a magnetic moment from its angular momentum; interaction leads to total angular momentum.
Page 17: Spin-Orbit Coupling Interaction
Spin-Orbit Coupling: Dependency on nuclear charge; strong for high-Z atoms affecting energy levels.
Page 18: Angular Momentum Variations
Angular Momentum Interaction: Interaction effects based on parallel or opposed orientation of magnetic moments, impacting energy level splitting.
Page 19: Total Electronic Angular Momentum
Total Angular Momentum (J): Combined from spin (s) and orbital (l) angular momentum.
Page 20: Example of Electron Configuration Calculation
Multiplicity from Electron Configuration: Example to determine values of l and s.
Page 21: Combining Angular Momentum Contributions
Method of Combining l and s: Demonstrates calculations for jz using allowed summation of components.
Page 22: Resulting j Values
Permitted j Values: Explained regarding their combinations and the impact of their orientations.
Page 23: Quantum State Description
Quantum States: Representation through microstates associated with configurations like 2P.
Microstates Count: Deduced using formulae, influencing electronic levels.
Page 24: Angular Momentum Summation
Angular Momentum Types: Explanation of configurations when combining l and s values, affecting energy states.
Page 25: Reinforcement or Opposition in Angular Momentum
Combination Methods: Outlined processes for angular momentum contributions (adding or opposing).
Page 26: Energy Term Labels
Energy Term Representations: Detailed how terms appear in configurations, explaining stability and configurations.
Page 27: Energy Levels as per Configurations
Configurations Example: Various electronic configurations and their corresponding energy levels described.
Page 28: Fine Structure Influence
Fine Structure Dependence: On energy levels and transition selection rules concerning allowed or forbidden transitions.
Page 29: Inclusion of Splitting Effects
Energy Splitting: Explicit connection of energy levels through visual diagrams, illustration of electronic states.
Page 30: Formation of Sodium D lines
Sodium Spectral Lines: Origin of observed spectral lines related to electron transitions in electronic configurations.
Page 31: Many Electron Atoms Characteristics
Overview of Electron Occupation: Similarity in orbital types but differing energies; highlights on Pauli’s and Hund’s principles.
Page 32: Closed Shell Definition
Closed Shell Concept: Electron configurations and their contributions to total angular momentum.
Page 33: Defining Orbital Angular Momentum
L Value Representation: Overall angular momentum states defined using term symbols and state representations.
Page 34: Orbital Contributions Calculation for Non-Equivalent Electrons
Energy Terms Calculation: By adding total angular momentum contributions, determining maximum and minimum values.
Page 35: Coupling Processes of Electrons
Coupling Methods for Electrons: Demonstration of orbital angular momentum based on unique electron configurations.
Page 36: Example for Non-Equivalent Electron Terms
Terms Determination: Explained through configurations identifying single and multiple electrons in orbitals.
Page 37: Summation Spins for Three Electrons
Spin Contributions: Calculating resulting energies and terms when more than two electrons involved.
Page 38: Spin Contributions Explained
Comprehensive Spin Contribution Methodologies: Summing methods based on odd and even electron configurations.
Page 39: Term Multiplicity
Multiplicity Calculation: How multiplicities relate to electronic configurations and identifications of states.
Page 40: Total Spin States of Electrons
Electrons with Half Spin: Resulting allowed configurations for cases with multiple electrons in unfilled shells.
Page 41: Spin Configurations for Two Electrons
State Representation: Overview of resultant configurations with pairs of electrons and their allowed spin values.
Page 42: Electrons Occupy Orientations
States Consideration: Neglecting completely filled shells when calculating term symbols for minimal energy.
Page 43: Closed Shells Contribution
Closed Shell Effects: Their lack of contribution to angular momentum impacting spectral properties of elements.
Page 44: Coupling Processes Explained
Hamiltonian Operators: Representation of electron interactions through different coupling terms.
Page 45: Total Angular Momentum Understanding
Single Electron Angular Momentum: Explained theory for total angular momentum in heavier elements with multiple electrons.
Page 46: Methods to Analyze Electron Contributions
Two Electrons Contributions Analyzing: How both methods work for analyzing angular momentum states.
Page 47: Permitted Values of Angular Momentum Quantum Numbers
j Values from Configuration: Explanation on permitted values derived from configurations.
Page 48: Relation Between j and L Values
Multiplicity versus States: How multiplicities relate to observable levels in configurations.
Page 49: Configuration Details for Specific Electron Cases
Examples of Specific Configurations: Analyzed within binding states, revealing significance of j values.
Page 50: Angular Momentum Contribution Collection
Methods Apply for Large Atoms: Russell-Saunders versus j-j coupling, understanding contributions.
Page 51: Establishing Term Symbols
Labeling States: Described through term symbols, emphasizing multiplicities and angular momentum.
Page 52: Electron Arrangement Stability
Lowest Energy State Arrangements: Guidance on stability and electronic configurations.
Page 53: Parameters for Molecular Term Symbols
Labeling Molecular States: Differences emphasized between atomic and molecular systems in labeling.
Page 54: Molecular Symmetry Considerations
Cylindrical Symmetry: Implications on angular momentum quantization.
Page 55: Molecular Orbital States Designation
Molecular Orbitals and Angular Momentum: Clarification on using Greek letters for state identification.
Page 56: Molecular Orbital Functionality
Interactions Between Atomic Orbitals: Displayed properties of bonding versus anti-bonding interactions.
Page 57: Total Orbital Angular Momentum
Total Orbital Angular Momentum: Represented through Λ combined from multiple electrons’ contributions.
Page 58: Spin Quantum Number Considerations
Total Spin Quantum Number Explained: Relevance across configurations.
Page 59: Spin-Orbit Coupling in Molecular Interactions
Effect of Spin on Angular Momentum: Interaction implications based on axial orientation.
Page 60: Total Angular Momentum and States
Z-Component of Angular Momentum: Definitions of z-component contributions compared against terms of energy states.
Page 61: Molecular Inversion Process
Wave Function Considerations: Explanation of g/u symmetry and their relevance to molecular states.
Page 62: Molecular Orbital Classifications
Class System of Molecular Orbitals: Discussion on bonding and anti-bonding types and their classifications.
Page 63: Overall Parity Determination
Parity Rules: Generating conditions based on occupied orbitals of states.
Page 64: Symmetric and Antisymmetric States
Labeling for Reflection Symmetries: Assigning states based on their behavior under reflection.
Page 65: Spin Multiplicity in Linear Molecules
Defining Quantities for Molecule's Characteristics: Different angular momentum designations including renaming multipliers.
Page 66: Molecular Configurations Explained through Examples
Example configurations Analyzed: Showcasing electronic status, multiplicities, and states.
Page 67: Illustrating B2+ Ion States
Description of Molecular Terms: Reflect on σ states, their assignments, and resulting terms.
Page 68: Sample Configurations Analysis
Observations of Molecular Orbital Contributions: Initial and excited state comparisons made clear.
Page 69: Understanding Configurations for Non-equivalent Electrons
Determinant States Analysis: Terms analyzed through multiple electron interactions displaying variations.
Page 70: Total Contributions for λ in Systems
Total Molecular Orbital Angular Momentum Quantification: Through specific electron configurations, showcasing total λ contributions.
Page 71: Current Molecule Examples with Their Limits
Respective Terms Comparison: Determining typical parity characters through comparisons of systems.
Page 72: Energy Ordering Observations
Hund’s Rule Application: Explains energy arrangement in electronic states for atomic configurations viably.
Page 73: Basics of Molecular Electronic States
Electronic States Completion: Various properties across diatomic molecules and their transitions.
Page 74: Selection Rules Summary
Transition Process Guidelines: Emphasizing essential conservation laws during transitions.
Page 75: Electronic Transition Overview
Molecular Reactions Upon Photon Absorption: How specific energy frequencies influence changes in states.
Page 76: Energy Order for Electronic Transitions
Photonic Influence on Electronic States: Expected ranges and transitions noted under conditions.
Page 77: General Observations on Potential Energy Curves
Potential Curves Representation: Different curves represent excited states and dynamics.
Page 78: Vibrational Analysis Associated with Energy States
Curves Comparison: Characterizing vibrational representations against equilibria under energetic states.
Page 79: Solving the Nuclear Schrödinger Equation
Finding Vibrational Level Associated: Each rotational level represented with vibrational levels discussed.
Page 80: Spectral Observations in Polyatomic Molecules
Labeling of States Variation: Depends majorly on symmetry and quantum angular momentum specifics.
Page 81: Transition Metals and Their Complexes
Introduction to Transition Metal Chemistry: Behavior and characteristics noted in molecular interactions and ligand attachment.
Page 82: d Orbital Conservation under Crystal Field
Orbital Splitting upon Arrangements: Describing energy arrangement concerning electron configurations.
Page 83: Octahedral Complexes Analysis
Coordination Influence and Orbital Interaction: Dispersion of electron states grounded within electron valency potentials.
Page 84: Absorption Energy Characteristics
Influence of Δo: Dependency on symmetry resulting in absorption changes spotted in visible regions.
Page 85: Tetrahedral vs Octahedral Configurations
Comparison of Setups: Noting orbital orders and energies transitioned concerning tetrahedral arrangements.
Page 86: d1 Configuration Considerations
Single Electron Impacts on term states during interactions with ligands.
Page 87: Octahedral Coordination and Configuration Changes
Describing Vertex Concentrations: Observing changes from state transitions and coordination types.
Page 88: Term State Analysis in Ligand Configurations
Electron Promotion Changes: Yielding a progressive understanding of term shifts through energetic levels.
Page 89: Free Ion Electromagnetic Responses
Spectroscopic Changes Analysis: Through configuration transitions and energy class differences.
Page 90: Spectroscopic States in d Configuration
Transition Analysis Across Levels: Coherent diagnostic for terms positioned on different configurations.
Page 91: Terms Splitting Discussion
Detailed Orbital Examination: Focused on symmetry and resulting term variation.
Page 92: Orbital Analysis on Transition Mechanisms
Charge Distribution Behavior: State-to-state transitions and their excitation frames analyzed.
Page 93: State Transition Explained
Comparative Analysis Across Complexes: Understanding energy orderings affected by electronic states.
Page 94: Transition Electron Assumptions
Terms Comparison through energy positionings governed by charge configurations elucidated.
Page 95: Absorptions Detailing in Specific Configurations
Identifying Spectroscopic Peaks Analysis: Noting transitions and detailing resonances observed.
Page 96: Electron Configurations in Octahedral Fields
Comparative d-d Transitions: Detailing similarities across configurations in questions to understand transitions involving d electrons.
Page 97: Example State Transition in Weak Fields
Characterization of Ground State Terms: Notable transitions through spectroscopic data.
Page 98: Weak and Strong Field Configurations
Differentiated Absorptions in Complexes: Imbued within spectroscopic bands and their resonances.
Page 99: Absorption Observations Across Similar Configurations
States Outcomes Acknowledged: Showcasing weak transitions via defined terms.
Page 100: Coloration from d Orbital Splitting
Connected Absorption Mechanisms: Understanding the impacts causing coloration in complex species.
Page 101: Titanium Spectral Analysis
Examining Specific Absorption Claims: Color properties linked with electronic transitions analytically.
Page 102: Absorption and Complementary Color Relations
Interactive Color Resulting Properties: Detailed implications on observed colors influenced by electron excitations.
Page 103: Molecular Orbital Energy Levels
Relative Placement Examination: Outlining bonding behavior and relative energy linked through shared orbitals.
Page 104: Absorption Spectrometer Functions
Functional Ranges and Electron Transitions: Spectroscopic barriers and elevation towards particular bonding levels noted.
Page 105: Important Electron Transitions
Critical Transitions for Absorption: Recognizing needed energy levels embedded within pi-bond structures.
Page 106: Radical Electron Transition Analysis
Comparative Studies for Energy Absorption: Noting molecular structures affecting their respective transitions and encompassing energy placements.
Page 107: Absorption Spectrum Examination
Absorption Rates in Absence of Bonds: Detailing transformations evidenced in colorless species and their corresponding transitions.
Page 108: Chromophore Absorption Traits
Energy Properties of Chromophores: Addressing energy transitions and tying them to specific characteristics.
Page 109: Delocalization Factors in Absorption Properties
Conjugation Influence: How it lowers energy gaps, directly associating increased absorption into higher wavelengths.
Page 110: Wavelength Shifts Observed with Conjugation
Diminishing Energy Gaps through Conjugation: Leading into the shifts across peak absorptions.
Page 111: Phenolphthalein Spectroscopic Analysis
Visible Absorption Characteristics: Discussing distinct behavior of phenolphthalein across different states.
Page 112: Summary of Excited Phenomena
Excited States Fluorescence and Phosphorescence: Detailed influencing internal and external transitions identified clearly.
Page 113: State Labeling for Polyatomic Molecules
Ground State Clarity Across Molecules: Identification and characteristics explained through changes in the molecular orbitals.
Page 114: Radiative vs Non-Radiative Processes
State Transition Dynamics: Exploring transitional behaviors between excited and ground states.
Page 115: Jablonski Diagram Functionality
Electronic and Radiative Transition Illustrations: Outlining important transitions seen through diagrams and flow motions.
Page 116: Processing Radiative Transitions
Vibration and Radiation Interaction: Detailing the process of excited states and their fading due to radiation._
Page 117: Internal Conversion Dynamics
Transformation Possibilities: Explanatory highlights around internal processes described functionally.
Page 118: Jablonski Diagram Inclusion
Energy State Representation: Fluorescent behavior due to internal transitions illustrated visually.
Page 119: Distinguishing Between Fluorescence and Phosphorescence
Differences noted in Emissions: Explaining the difference between transient stages versus prolonged emissions seen in phosphorescence.
Page 120: Fluorescence Mechanism Overview
Radiative Emissions Post Absorption: Detailed relationships in transition states experienced.
Page 121: Molecule Behavior Post-Excitation
Retention of Energy Post Absorption: Internal interactions leading to electron retention and emission behaviors.
Page 122: Frequency Shifts and External Influences
Color Shift Dynamics: Impacts based on surrounding environmental shifts.
Page 123: Principles of Phosphorescence Extraction
Transition through Triplet States Importance: Analysis on transition impacts and energy movement noted.
Page 124: Effect of Intersystem Crossing on Transitions
Role of Spin Dynamics: Discussing crossing dynamics among states impacting observable emissions.
Page 125: Endurance of Phosphorescence Confirmed
Slow Energy Release Dynamics: Expounding on retention and delayed emission due to surrounding interactions.
Page 126: Solid Sample Focus on Phosphorescence
Intensity Derivations Highlighted: Enhanced focus on solid-state capabilities leading to distinct emissions.