Backbonding Backbonding is a type of resonance. Back bonding increases stability. It does affect properties of molecules, like Hybridisation & Dipole moment.

Slides:



Advertisements
Similar presentations
MOLECULAR SHAPE HOW DOES SHAPE AND POLARITY DETERMINE FUNCTION AND PROPERTIES OF MOLECULES?
Advertisements

Chemical Bonding Why? To achieve stability (happiness)  Lower energy level  8 electrons –react so as to achieve the valence level configuration of NEAREST.
Photoelectron Spectroscopy Lecture 9: Core Ionizations –Information from core ionization data –Separating charge and overlap effects Jolly’s LOIP Model.
Bonding Theories Summary Edward A. Mottel Department of Chemistry Rose-Hulman Institute of Technology.
Chapter 9 Chemical Bonding Theories Valence Bond Theory: Uses Lewis Structures Bonds form using shared electrons between overlapping orbitals on adjacent.
Properties of Bonds Polarity Bond Order Bond Length Bond Energy.
Chapter 10 Chemical Bonding Theories Valence Bond Theory: Uses Lewis Structures Bonds form using shared electrons between overlapping orbitals on adjacent.
Transition Metal Complex Bonding and Spectroscopy Review
Hybrid Orbitals: atomic orbitals formed by blending different orbitals together Just like with other hybrids, the characteristics of the hybrid orbitals.
Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals Chapter 10 Copyright © The McGraw-Hill Companies, Inc. Permission required.
AP Chapter 9 Molecular Geometry and Bonding Theories HW:
Copyright © Houghton Mifflin Company. All Rights Reserved.1 Chemistry 6/e Steven S. Zumdahl and Susan A. Zumdahl Chapter 9: COVALENT BONDING: ORBITALS.
Covalent Bonds and Structures Chemistry 11 Ms. McGrath.
Valence Bond Theory. How do bonds form? The valence bond model or atomic orbital model was developed by Linus Pauling in order to explain how atoms come.
Chapter 8 sections 1-7 Chapter 9 sections 1-6 Ionic – Formed by the electrical attraction of a positive cation to a negative anion. Don’t worry about.
Ψ 1 = c 1 φ 1 + c 2 φ 2 ψ 2 = c 1 φ 1 - c 2 φ 2 Molecular Orbital Theory LCAO-MO = linear combination of atomic orbitals Add and subtract amplitudes of.
Chapter 9 Chemical Bonding Theories
Alcohols and Ethers-2 Dr AKM Shafiqul Islam School of Bioprocess Engineering University Malaysia Perlis (UniMAP)
Chemistry 100 Chapter 9 Molecular Geometry and Bonding Theories.
Molecular Orbital Energy Diagrams (16.7) MO energy diagrams are useful in that they show how atomic orbitals from different atoms may combine to molecular.
Atomic QM to Molecular QM ( ) Solution of SE for molecules is more complicated due to much larger number of electrons and multiple nuclei – SE.
Dipole Moments and Polar Molecules 10.2 H F electron rich region electron poor region    = Q x r Q is the charge r is the distance between charges.
Molecular Orbital Theory (What is it??)  Better bonding model than valence bond theory  Electrons are arranged in “molecular orbitals”  Dealing with.
Chemical Bonding II – Molecular Geometry and Hybridisation of Atomic Orbitals General Chemistry I CHM 111 Dr Erdal OnurhanSlide 1 Molecular Geometry of.
Chemistry 1011 Slot 51 Chemistry 1011 TOPIC Acids and Bases TEXT REFERENCE Masterton and Hurley Chapter 4.2 (Review), 13, 14.1, 15.1 (page 427), 21.2 (page589)
Valence Bond Theory Orbital shapes, Individual (“isolated”) Atoms.
Factors Affecting Solubility pH Common Ion Effect Formation of Complex Ions.
Covalent bonding: Overlapping of 2 half filled orbitals Gases.
Title: Lesson 5: Lewis Acids and Bases Learning Objectives: – Understand that a Lewis acid is a lone pair acceptor and a Lewis base is a lone pair donor.
Hybridization: Localized Electron Model
Hybridization and Other Good Stuff. Introduction A hybrid results from combining two of the same type of objects, and it has characteristics of both Atomic.
Coordinate Covalent Bond Ammonia NH 3 to Ammonium Ion [NH 4 ] + One atom contributes both electrons in a bond.
Chapter 9 Chemical Bonding Theories
Section 12.3 Lewis Structures 1.To learn to write Lewis structures 2.To learn to write Lewis structures for molecules with multiple bonds Objectives.
Carbon’s valence electrons?. Hybrid Orbitals  Mixing of valence shell orbitals to form new similar orbitals for bonding electrons.
Bell Work  Bonding / Chap 8 Reading Is Due Today!  Pick Up Note Sheet  Pick Up & Complete Bell Work.
1 Molecular Geometry and Hybridization of Atomic Orbitals.
Part 1: Molecular Orbitals
Ligand Field Theory: σ Bonding
Atomic Bonding Mrs. Silvia.
Electron Counting Methods Electron Counts for [MXaLb]c+
Molecular Orbital Theory
MOLECULAR ORBITAL THEORY
Covalent Bonding: Orbitals
Chapter 9 Chemical Bonding Theories
Valence Bond Theory.
Rules for Predicting Molecular Geometry   1.  Sketch the Lewis structure of the molecule or ion 2.  Count the electron pairs and arrange them in.
Chapter 9 Valence Bond Theory.
Electron Dot Structure or Lewis Dot Structures
Molecular Orbital Theory
Sigma (s) and Pi Bonds (p)
Part 1: Molecular Orbitals
Molecular Shapes and Hybrid Orbitals
Chapter 9 Chemical Bonding Theories
Notice the numbers on the diagram.
Covalent bonds are formed by:
CH 14-2 Characteristics of Benzene
Physical Chemistry Chapter V Polyatomic Molecular Structure 2019/4/10
Molecular Shapes.
CHEMICAL BONDING Molecular Orbital Theory Valance Bond Theory
Isomerism: two main kinds
Molecular Orbitals Two interacting orbitals make two new orbitals. Using a 1s orbital on two H atoms: anitbonding orbital = higher energy bonding orbital.
Bond Theories.
Covalent bonding review
DEPARTMENT OF CHEMISTRY
PREPARATION AND PROPERTIES OF METALLIC CARBONYLS
POSTULATES Condition for bond formation Strength of the bond
Chapter 9 Chemical Bonding Theories
Rotation about single and multiple bonds
Electron Dot Structure or Lewis Dot Structures
Presentation transcript:

Backbonding Backbonding is a type of resonance. Back bonding increases stability. It does affect properties of molecules, like Hybridisation & Dipole moment. In Π back bonding, the electrons move from an atomic orbital on one atom to a π* anti-bonding orbital on another atom or ligand.

pπ-pπ bonding P - Pi p - Pi bond is formed when one p orbital of each combining atom is overlapped laterally. P - Pi d - Pi bond is formed when p orbital of one atom and d orbital of another atom overlap laterally.

dπ-pπ back bonding In this electrons are donated from filled d- orbitals of the metal to the empty d-orbitals of the ligand. pπ– pπ bonding: In this type of bonding p-orbital of one atom overlap sideways with p-orbital of another atom which results in the formation of π-bond, known as pπ– pπ bond.

BI3>BBr3>BCl3>BF3.this trend is due to pie back bonding. All halides have lone pairs, they donate one lone pair to boron by overlapping with the p orbital of boron. Effective overlap between orbital’s decreases due to large size of p orbital of halides.Hence,electron deficiency of boron atom in its halides follow the trend--BI3>,BBr3,>BCL3>BF3 and so it is the Lewis acidity ORDER. A species which is more electron deficient will electron easily and hence will be more acidic.

A stress on metal-carbonyl bond

MO diagram of CO

Alkene with metals