Fundamentals of Materials Science and Engineering
LearningObjectives
After careful study of this chapter you should be able to do the following: 1. Name the two atomic models cited, and note the differences between them. 2. Describe the important quantum-mechanical principle （量子 理论）that relates to electron energies. 3. (a) Schematically plot attractive, repulsive, and net energies versus interatomic separation for two atoms or ions. (b) Note on this plot the equilibrium separation and the bonding energy. 4. (a) Briefly describe ionic, covalent, metallic, hydrogen, and van der Waals bonds. (b) Note what materials exhibit each of these bonding types.
Fundamentals of Materials Science and Engineering
Chapter 2 Atomic Structure and Interatomic Bonding
Covalent Bond(SiO2 B2O3)
Metallic bond
Fundamentals of Materials Science and Engineering
Hale Waihona Puke tabulate vt. 列成表格 Pauli exclusion principle 包 利不相容原理 tungsten 钨 Predominate支配 掌握 typify 作为 的代表 Proton 质子 valence electrons价电子 Quantize 使量子化
Fundamentals of Materials Science and Engineering
Ion离子 Ionic 离子的 Cation阳离子↔ Anion阴离 子 Isotopes 同位素 Magnitude 大小 量级 shield 防护物质 Mercury汞 Mole 摩尔 spatial orientation 空间取向 Neutron 中子 Overlap 交叠

Fundamentals of Materials Science and Engineering
Introduction

Some of the important properties of solid materials depend on geometrical (几何的) atomic arrangements (原子排 列), and also the interactions that exist among constituent (component 组元、成分) atoms or molecules. This chapter, by way of preparation for subsequent discussions, considers several fundamental and important concepts, namely: atomic structure (原子结构), electron configurations (分布) in atoms and the periodic table(周 期表), and the various types of primary and secondary interatomic bonds that hold together the atoms comprising (consisting of ) a solid. These topics are reviewed briefly, under the assumption （假设） thatsome of the material is familiar to (为熟悉) the reader.
Fundamentals of Materials Science and Engineering
What should you be able to do after studying this chapter?
Name and explain the primary or chemical bond found in solids.
Fundamentals of Materials Science and Engineering
This micrograph (图片), which represents the surface of a gold specimen, was taken with a sophisticated （complex复杂的） atomic force microscope (AFM) （原子力显微镜）. Individual atoms for this (111) crystallographic surface plane （晶面）are resolved（分辩的）. Also note the dimensional scale(标 尺) (in the nanometer (纳米) range) below the micrograph.
Important terms and concepts



Symmetrical 对称的 ↔ asymmetrical不对称的 Coulombic force 库仑力 covalent 共价的 ~bond 共价键 ductile Easily molded or shaped. 可塑的，易成形的，可延展的 ≈malleable electronegative 负电性的 ↔ electropositive阳电性的（正电性的） parameter ：variable 参数 quantum mechanics 量子力学 repulsive 排斥的 ↔attractive scale 刻度 Schematical: in the form of a scheme or diagram 图解的 solidification 凝固 固化 /Liquefaction 液化↔ melting superscript 上标 ↔ subscript 下标 valence electrons 价电子 vibration 振动
Fundamentals of Materials Science and Engineering





glue 胶合 Computation 估计 ground state 基态 Coulomb 库仑 Covalent 共价的 hybrid 杂化 Diatomic 二价的 Dipole 偶极子 induced dipoles诱导偶极子 inert : inactive惰性的 ↔active Intrinsical本质的 固有的 quantum mechanics量子力学
Fundamentals of Materials Science and Engineering




Actinide 锕类 Adjacent 附近的 Alkali: caustic/basic 碱性的 ↔acidic 酸性的 neutral 中性的 Alkaline earth 碱土 Ambient周围的 环境的 Fluctuating: vibrating 变动 Bismuth铋 halogen 卤素 fluorine氟 Bohr玻尔
Fundamentals of Materials Science and Engineering
ATOMIC STRUCTURE
2.2 FUNDAMENTAL CONCEPTS Each atom consists of a very small nucleus（pl. nuclei原子核） composed of protons (质子) and neutrons (中子), which is encircled (encompassed 围绕) by moving electrons (电子). Both electrons and protons are electrically charged (带电的), the charge (电荷) magnitude (数量) being 1.60 × 10-19 C, which is negative in sign for electrons and positive for protons; neutrons are electrically neutral. (translation ) Masses for these subatomic particles are infinitesimally (Immeasurably or incalculably minute 无穷小的) small; protons and neutrons have approximately (about) the same mass, 1.67× 10-27 kg, which is significantly larger than that of an electron, 9.11 × 10-31 kg.
Fundamentals of Materials Science and Engineering