A Very Brief Introduction to Boron Chemistry

Slides:

Advertisements

Similar presentations

The one that is lower in energy is called the bonding orbital, The one higher in energy is called an antibonding orbital. These two.

Advertisements

3.2- EXPLAINING MOLECULAR FORMULAS Molecular Substances.

Parts of an Atom FlipChart 1st Flap – Write Parts of an Atom 2 nd Flap – Atom –write the definition for atom 3 rd Flap – Neutron –What charge does a neutron.

Chapter 12,13. He Ne Ar Kr Xe Rn The Periodic Table of the Elements CrMnFeCoNi Mo W Tc Re Ru Os Rh Ir Pd Pt Most Probable Oxidation State _4-

Lecture 19 Electron count in cluster compounds 1) Electron count in boron cages. Wade’s and Mingos’s rules The cluster electron count in closo-polyboranes:

1 Electron counting rules and simple bonding descriptions for electron-poor materials  -SiB 3.

Electron Deficient Molecules Boron Hydrides Edward A. Mottel Department of Chemistry Rose-Hulman Institute of Technology.

Lecture 17 Molecular Orbital Theory 1) Molecular Orbitals of AH x (x = 3, 4, 6) MO diagrams can be used on a qualitative basis to understand the shape.

Molecular Orbital Theory Atomic orbitals mix together and make: – Bonding Orbitals Electrons in these orbitals help hold atoms near each other – Antibonding.

Semiconductors and Superconductors Ashley Heady 510 Advanced Inorganic.

Molecular Orbital Theory

Electron Deficient Molecules Boron Hydrides Edward A. Mottel Department of Chemistry Rose-Hulman Institute of Technology.

Part A: Atomic Structure

Introduction to ATOMS. Electrons are always on the move.

 The atoms of all elements are made up of a central nucleus with orbiting electrons. ◦ A nucleus is made up of positively charged PROTONS and neutral.

CHEM 5013 Applied Chemical Principles

Introduction to Chemistry Bohr Models and Lewis Dot Structures

When does the octet rule fail?. H, He and Li Helium strives for 2 valence electrons –1s 2 configuration Hydrogen will sometimes will share its one electron.

Atoms, Ions, Molecules and Polarity

The Atom and Its Parts Physical Science.  The three subatomic particles are:  Proton – Positive charge  Electron – Negative charge  Neutron – No charge.

4 – Investigate and describe the compounds formed by bonding elements. 3 – Describe why certain elements bond with others. 2 – Use the periodic table.

Focus on Valence Electrons: Draw valence for Na and Cl: NaCl What will happen when the two elements are combined? Na will transfer 1 electron to Cl Now,

8.4 DETERMINING MOLECULAR SHAPES. THE MODEL WE WILL USE TO DETERMINE MOLECULAR SHAPE IS CALLED _________ (V_____________ S_________ E_____________ P________.

Chapter 3 Atoms and Elements 3.4 Atomic Number and Mass Number 1 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition.

ACTIVE LECTURE QUESTIONS Barbara Hunnicutt Seminole Community College Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings 2 Basic.

Inorganic Chemistry - Atomic Structure Biology 2121 Chapter 2 Biology 2121 Chapter 2.

Molecular Orbital Theory Molecular Orbitals Just as atomic orbitals belong to a particular atom, a molecular orbital belongs to molecules as a whole.

DIBORANE. Methods Of Preparetion It is prepared by treating boron Trifluoride with LiAlH4 in diethyl ether 4BF 3 + 3LiAlH 4 2B 2 H 6 +3LiF + 3ALF 3 In.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case M I C R.

Minerals – Chemistry Review. Minerals are made up of different chemical elements bound together.

The Mighty Electron.

Identify the name of the element Carbon (C). 6 protons (Atomic # 6)

Atoms Elements Molecules Compounds Ions Organic vs. Inorganic.

Introduction to Molecules Living things can be organized into several different levels or tiers of structure. The most basic of these is the molecular.

Chemistry Notes Dot Diagrams Ionic Bonding Diagrams.

Chemistry PODs POD #73 11/30/2015 Write your first and last name and today’s date in the upper right hand corner of your paper. Fold your paper.

Chapter 4 An Introduction to Organic Reactions. 4.1 General Principles of Organic Reactions A.Types of Reactions; The Reaction Equation In an organic.

CHEMISTRY PART 2 Periodic Table.  Atomic Number = # of protons  If the atom is neutral:  Atomic Number = # of electrons  Atomic Mass = # of protons.

CHEMISTRY PART 2 Periodic Table.  Atomic Number = # of protons  If the atom is neutral:  Atomic Number = # of electrons  Atomic Mass = # of protons.

Unit 1 Chemical Bonding: Ionic 1.3 What are ions and how do they form? AIM: How do ions form and why? DO NOW: Draw the Planetary Model of the following.

What determines the properties of an atom or molecule? 6 th Grade Gifted Chapter 4 – Chemical Reactions.

Fundamentals of Organic Chemistry Chapter 1. What is Organic Chemistry? Old Timers View: Something with vital forces! Now: Chemistry of carbon-containing.

Tutorial 1) Using Slater’s rule conﬁrm that the experimentally observed electronic conﬁguration of K (Z = 19), 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1, is energetically.

Inside An Atom. Nucleus Every Atom has a core called a nucleus. Every Atom has a core called a nucleus. The Nucleus is largest part of an atom (about.

1 Compounds and Their Bonds Octet Rule and Ions Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings.

Chapter 5 Valence electrons.

Part A: Atomic Structure

Inorganic Chemistry - Atomic Structure

WARM UP “We never touch people so lightly that we do not leave a trace.” –Peggy Tabor Millin What does this mean to you? How might this impact the way.

New Directions for Higher Boranes

Chemistry Part 2 Periodic Table.

3. Show the method of balancing an equation for Mg + O -> MgO

Chapter 6 Valence electrons.

Chapter 7 Ionic and Metallic Bonding 7.1 Ions 7.2 Ionic Bonds and

Introduction to the Periodic Table

A brief review of Lewis Acids and Bases

Atoms and Elements.

Chemistry-Part 1 Inside the Atom

3. Show the method of balancing an equation for Mg + O2 -> MgO

A brief review of Lewis Acids and Bases

A brief review of Lewis Acids and Bases

A brief review of Lewis Acids and Bases

Subatomic Particles Neutron Proton Electron

3rd Nine Weeks Assessment Review

The band structure shows that the system is metallic.

Periodic Table How to Draw Bohr Diagrams

Chemistry Lewis Structures

Molecular Biology Inorganic Chemistry.

Presentation transcript:

A Very Brief Introduction to Boron Chemistry Kristina Orosz Nov. 5, 2004

Uses of Boron Borosilicate glass-pyrex Detergents Flame retardants Ceramics Pyrotechnics Used in production of impact resistant steels Control rods in nuclear reactors

Common Bonds in Boranes 2c-2e- B-H 3c-2e- B-H-B 2c-2e- B-B 3c-2e- B-B-B

Diborane B2H6 Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publisher, 1993. 790.

B2H6 MO Diagram Wade, K. Electron Deficient Compounds. London: Nelson, 1971. 30.

Tetraborane B4H10 Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publisher, 1993. 794.

Dodecaborane [B12H12]2- Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publisher, 1993. 795.

Elemental Forms of Boron b-rhombohedral, B12(B12)12, (B12)(B12)(B60) a- rhombohdral Housecroft, C. E.; Sharpe, A. G. inorganic Chemistry. New York: Pearson Education Limited, 2001. 251-2.

Boron Deltahedra – Parent Clusters Housecroft, C. E.; Sharpe, A. G. inorganic Chemistry. New York: Pearson Education Limited, 2001. 275.

Boron Hydrides Housecroft, C. E.; Sharpe, A. G. inorganic Chemistry. New York: Pearson Education Limited, 2001. 272.

Huheey, J. E. ; Keiter, E. A. ; Keiter, R. L Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publishing, 1993. 799.

Wade’s Rules n = number of B atoms in parent closo-deltahedron Always n+1 bonding e- pairs and n+1 bonding MOs nido has n-1 vertices arachno has n-2 vertices hypho has n-3 vertices

Using Wade’s Rules Determine number of remaining hydrogen atoms Find parent closo-deltahedron Find total available bonding e-s: “sew up” hole with H atoms Each vertex has a H Lose highest connectivity B first then lose adjacent sites Is it closo, nido, arachno, hypho? n+1 bonding e- pairs Overall charge Each additional H gives 1 e- Each B-H unit gives 2 e-s Try to keep it as symmetrical as possible Low connectivity B atoms can get another 2c-2e- B-H bond Bridging H atoms Using Wade’s Rules

Huheey, J. E. ; Keiter, E. A. ; Keiter, R. L Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publisher, 1993. 798.

Carboranes C2B10H12 ortho meta or neo para Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry: principles of structure and reactivity, 4th ed. New York: HarperCollins College Publisher, 1993. 801.

Boron Neutron Capture Therapy (BNCT) 10B has large cross-section for neutron capture 10B +  a + 7Li Products can kill cells Cancer treatment Cages - need high [10B] in cell

References Dreiss, Matthias, ed., and Heinrich Nöth, ed. Molecular Clusters of the Main Group Elements. Weinheim: Wiley-VCH, 2004. 95-125. Housecroft, Catherine E. Boranes and Metallaboranes: structure, bonding, and reactivity. 2nd ed. New York: Ellis Horwood, 1994. 1-20, 93-116. Housecroft, Catherine E., and Alan G. Sharpe. Inorganic Chemistry. New York: Pearson Education Limited, 2001. 245-279. Huheey, James E., Ellen A. Keiter, and Richard L. Keiter. Inorganic Chemistry: principles of structure and reactivity. New York: HarperCollins College Publishers, 1993. 789-801. Wade, Kenneth. Electron Deficient Compounds. London: Nelson, 1971. 1-61.