复旦大学：《物理化学》精品课程教学资源（PPT课件讲稿）第3章 共价键理论和双原子分子结构 Molecular Structure and Bonding

●物理化学 Physical chemistry 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 1 Physical Chemistry

●物理化学 Children's Song I try to do my best each day, In my work and in my play; And if always do my best, need not care about the test 2021/8/21 复旦大学化学系 g

物理化学I 2021/8/21 复旦大学化学系 2 Children’s Song I try to do my best each day, In my work and in my play; And if I always do my best, I need not care about the test

●物理化学 Chapter Three Molecular Structure and bonding The force of attraction between two atoms or ions that hold them together in a unit is called chemical bond 零线 What is the nature of Chemical bond? The History Ideas 2021/8/21 复旦大学化学系 B

物理化学I 2021/8/21 复旦大学化学系 3 The force of attraction between two atoms or ions that hold them together in a unit is called Chemical Bond What is the nature of Chemical Bond? ----The History Ideas Chapter Three Molecular Structure and Bonding

●物理化学 3-1 Covalence bond Theory W.Kossel: one or more electrons from one atom atls are removed and attached c my D dfna to another atom, resulting in positive and negative g ae de ions which attract each 几kx other--c-ionic binding G W.Lewis: one or more pairs ofelectrons are shared by two atoms covalent binding G W.Lewis 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 4 W.Kossel : one or more electrons from one atom are removed and attached to another atom, resulting in positive and negative ions which attract each other----ionic binding G.W.Lewis: one or more pairs of electrons are shared by two atoms ---- covalent binding 3-1 Covalence bond Theory G.W.Lewis

●物理化学 3-1 Covalence bond Theory B L Be B 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 5 3-1 Covalence bond Theory

●物理化学 3-1 Covalence bond Theory Covalent and lonic Binding F Contour maps of the molecular charge distributions of n, and LiF at their equilibrium internuclear separations 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 6 Contour maps of the molecular charge distributions of N2 and LiF at their equilibrium internuclear separations Covalent and Ionic Binding 3-1 Covalence bond Theory

●物理化学 3-1 Covalence bond Theory The hamiltonian of h is 十 21222M"a2M R, r=Ey(R,r) ro2 b rh2 Rab rir The underlying physical laws necessary for the mathematical theory of.. the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble. -Dirac 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 7 The Hamiltonian of H2 is (R,r) E (R,r) M M r r r r R r a a b b a b a b   =       −  −  −  −  − − − − + + 1 2 1 2 1 2 2 2 2 2 2 1 1 1 1 1 1 1 2 1 2 1 2 1 2 1 The underlying physical laws necessary for the mathematical theory of … the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble. ----------Dirac 3-1 Covalence bond Theory

●物理化学 3-1 Covalence bond Theory +n+v(R,r)=EV(R 2 2M 2M 12 R B.O. Approximation 2 b2 2 R Oppenheimer a b +n+u(r)=E(R)u(r) 72 2 tb 12 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 8 Rab 12 r b2 r a1 r a b 1 2 a2 r b1 r (R,r) E (R,r) M M r r r r R r a a b b a b a b   =       −  −  −  −  − − − − + + 1 2 1 2 1 2 2 2 2 2 2 1 1 1 1 1 1 1 2 1 2 1 2 1 2 1 (r) E(R) (r) r r r r R r a a b b a b   =       −  −  − − − − + + 1 2 1 2 1 2 2 2 2 1 1 1 1 1 1 1 2 1 2 1 B.O. Approximation Oppenheimei 3-1 Covalence bond Theory

●物理化学 3-1 Covalence bond Theory 111111 V V(r)=E(Ry(r) 2 2 a2 b2 b 12 Separate variables E HEitler and elondon's contribution 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 9 ( ) ( ) i i i i ai bi i U r r E r r r   =       −  − − + ( ) 1 1  2 1 2 (r) E(R) (r) r r r r R r a a b b a b   =       −  −  − − − − + + 1 2 1 2 1 2 2 2 2 1 1 1 1 1 1 1 2 1 2 1 Separate Variables W.Heitler and F.London’s contribution 3-1 Covalence bond Theory

●物理化学 3-1 Covalence bond Theory 11 +n+y/(r)=E(R)(r) 2 b2 R Linear variational method Trial Eigenfunction =C1W1+C2v2 v1=v(1)(2)v2=V2(26(1 2021/8/21 复旦大学化学系

物理化学I 2021/8/21 复旦大学化学系 10 (r) E(R) (r) r r r r R r a a b b a b   =       −  −  − − − − + + 1 2 1 2 1 2 2 2 2 1 1 1 1 1 1 1 2 1 2 1 Linear Variational Method (1) (2) 1 = a b (2) (1)  2 = a  b Trial Eigenfunction  = C1 1 +C2 2 3-1 Covalence bond Theory