Thus bonds are made up of attractive and repulsive forces. Ionic solids consist of positively and negatively charged ions held together by electrostatic forces. Lecturer at saraswati college of engineering, navi mumbai. This energy varies depending on the type of bonding. Chemical bonding module 2 notes atomic structure and chemical bonding e formation of nacl from sodium and chloride ions. Contents preface 1 bonding in solids 2 crystal structures and xray diffraction 3 principles of quantum mechanics 4 electron. The major types of solids are ionic, molecular, covalent, and metallic. The interatomic forces are basically selection from engineering physics book. In metallic solids and network solids, however, chemical bonds hold the individual chemical subunits together. Pdf most of the engineering materials are alloys solid solutions and inevitably contain some impurities or. View table of contents for interatomic bonding in solids. Grimes encyclopedia of life support systems eolss fluorine n 9 is a dimolecular gas f2, neon n 10 is a monatomic inert gas but sodium n 11 is a soft metallic solid. These forces consist of both attractive and repulsive forces.
Space lattice, unit cell, lattice parameters, crystal systems,bravais lattices, miller indices, crystal planes and. Unesco eolss sample chapters materials science and engineering vol. All solids are composed of atoms that are bonded together. In metallic solids, the valence electrons are no longer exclusively associated with a single atom. A covalent bond may also be formed when two or more atoms of different nonmetals share one or more pairs of valence electrons. Pdf hardness and elastic properties of covalentionic solid.
The value of the energy needed to move an atom completely away from its equilibrium position is a measure of the binding energy also called the cohesive energy between them. A covalent bond is formed, when two or more electrons of an atom, in its. Solid state physics l bonding in solids metals, isolators, semiconductors l classical free electron theory of metals l quantum theory of metals l band theory of solids l semiconductors llasers physics 215 winter 2002 prof. A prototypical example is the sodium chloride crystal, as we discussed earlier. Ionic bond, covalent bond, metallic bond, hydrogen bond, vanderwaals bond. View of bonding in extended structures roald hoffmann. Ionic bond, covalent bond, metallic bond, hydrogen bond, vanderwaals bond, calculation of cohesive energy. The crystal is essential a single, macroscopic molecule with continuous chemical bonding throughout the entire structure. Introduction bonding in solids ionic bond covalent bond.
As the name implies, metallic bonding is responsible for the formation of metallic crystals. Relation between bonding, structure and properties of materials introduction bonding in solids ionic bond covalent bond metallic bond intermolecular forces 1 materials science and engineering sophia a. Article pdf available in journal of applied physics. I bonding in solids, structural and chemical properties r. Grimes encyclopedia of life support systems eolss lowest energy configuration of the neutral atom. Electrons transfer from sodium atoms to adjacent chlorine atoms, since the valence electrons in sodium are loosely bound and chlorine has a large electron affinity. Ionic solids tend to have high melting points and are rather hard. The bonding may be of different nature depending upon the constituent atoms and the prevalent. In order to comply with paulis exclusive principle, the shared two electrons should be of opposite direction. Engineering physics pdf notes enginering physics notes. Physics for engineers volume 1 january engineering physics1 3e for anna university pb. The valence electrons are essentially free of the atoms and are able to move relatively easily throughout the metallic crystal.
Bonding is due to the attractive forces between the positive ions and the conduction electrons. A crystal consists of atoms or molecules bound by interatomic forces or bonds. The interatomic forces are basically electrostatic in nature. Bonding in solids, structural and chemical properties.
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