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发表于 2004-10-29 19:27:37
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Chapter 7 Coordination Compounds 配位化合物
Definition 定义
A coordination compound 配位化合物 is one in which the metal ion or atom is bonded to one or more neutral molecules or anions so as to be a defined and integral structural unit. Often, we call it coordination complex. 配位化合物是中心原子与一定数量的分子或离子形成的具有一定的空间结构的配离子或分子，有时称络合物。
Central Atom, Ligand, and Coordination Bonding 中心原子、配体和配位键
The metal ion or atom is called central ion or atom. 金属原子或离子为中心离子或原子
The molecules or ions bonded to the central metal ion are called ligands 配体. For example, NH3, Cl etc. 与中心原子键合的分子或离子称为配体。
The ligands donate the lone pair electrons to the central metal to form the covalent bondings, called coordination bondings. 配体提供原子对与金属原子形成的共价键称为配位键。
Coordination Ion, Coordination Atom 配离子，配位原子
Mn+ + NH3  [MNH3]n+, coordination ion 配离子
In ligands, the atom which donates its lone pair electrons to the central ion is called coordination atom 配体中，提供电子对与金属原子形成配位键的原子，称 为配位原子.
If a ligand has more than one coordination atom is called polydentate or “many-toothed” 配体中，若有多个配位原子，称为多啮配体.
Chelate螯合物
the complex formed between a central and one or several polydentate ligand(s) 多啮配体 is called a chelate. 与多啮配体形成的配合物，称为螯合物。For example, Cu(en)22+, 二乙二胺合铜(II)
Here, en: NH2CH2CH2NH2, ethylenediamine 乙二胺.
Some Common Ligands常见配体
Bidentate and Polydentate Ligands
Nomenclature of Coordination Compounds 配合物命名
if a coordiantion compound is ionic, name the cation first and the anion second. 先命名阳离子，再阴离子
name the ligands first, followed by the central metal. 在配离子中，先命名配体，再命名金属。
name the ligands alphabetically按字母顺序命名配体. Negative ligands (anions) have names formed by adding “o” to the stem name of the group. For example, O2 oxo, NO3 nitrato.
use the numeric prefix to indicate the number of ligands present. 用数字前缀表示配体数量。
2: di 或 bis；3: tri 或 tris；4: tetra 或 tetrakis etc.
Examples of the Names of Complexes 配合物命名范例
K3[Ag(S2O3)]
potassium bis(thiosulfato)argentate(I). 二硫代硫酸根合银(I)酸钾。
[Co(en)(NO2)Cl2] dichloroethylenediaminenitrocobaltate(III).二氯二硝基乙二胺合钴(III)配离子。
[Cu(NH3)4]SO4
tetraamminecopper(II) sulfate 硫酸四氨合铜(II)
[Co2(CO)8]
octacarbonyl dicobalt(0) 八羰基合二钴。
Valence Bond Theory价键理论
The nature of metal-ligand bond is the coordination covalent bond. 配位键本质上是共价键。
The electron pair from the ligand is shared with the metal. 配体提供电子对与金属离子共享。
This electron pair occurs one of several equivalent hybrid orbitals on the metal. 电子对占据了金属离子的某个杂化轨道。
The Spatial Structures of Complexes配合物的空间构型
The Complexes of d10 Metal Ion
The Complexes of d8 Metal Ion(Tetrahedron)
The Complexes of d8 Metal Ion(Planar Square)
Tetrahedral and planar square
The Complexes of d5~7 Metal Ions(Octahedron)
The Complexes of d5~7 Metal Ions(Octahedron)
Inner Orbital Complexes and Outer Orbital Complexes
inner orbital complex 内轨型配合物, sometimes called low spin complex 低自旋配合物
The d orbitals from inner d subsell are hybridized with the outer s and p orbitals to form of a set hybrid orbitals. 内层d轨道与外层s、p轨道杂化，形成杂化轨道。
Outer orbital complex 外轨型配合物, sometimes called high spin complex 高自旋配合物
Octahedral complexes
Crystal Field Theory 晶体场理论
d Orbitals in Octahedral Field
Split Energy , 分裂能
As ligands approach the metal to form bonds, there are repulsion between the electrons of the metal and ligands. This repulsion between the positive metal ion and negative ligand lone pair are electrostatic. Thus, the degenerate d orbitals of a free atom or ion are split.
配体靠近中心离子成键时，配体中的孤对电子与中心离子的d电子互相排斥，引起简并的d轨道发生分裂。
Split Energy in Octahedral Field
The Magnitude of Split Energy分裂能的大小
the nature of the ligands; 配体性质
Different ligands have the different split energy.
the charge on the metal ion; 金属离子的电荷
the more positive the charge is, the greater split energy.
whether the metal is in the first, second or third row of transition elements..金属原子的周期数
the 2nd or 3rd metal ions have larger split energy.
Weak Field Ligands and Strong Field Ligands弱场配体和强场配体
Ligands which cause only a small degree of crystal field splitting are termed weak field ligands 导致晶体场分裂能小的配体，称为弱场配体, otherwise are strong field ligands 导致晶体场分裂能大的配体，称为强场配体.
Spectrochemical Series 光化学序列
Weak Field and Strong Field
The Split Energies of 1st Series of Transition Metal Ions
High-spin and Low-spin Complexes 高自旋、低自旋配合物
Electron Pairing Energy and Split Energy电子成对能和分裂能
According to Hund’s rule, it requires the electron pairing energy P 电子成对能 when the unpaired electrons in Mn2+ ion are forced to be paired. 根据洪特规则，判断Mn2+的电子是否成对，就引入电子成对能这一物理量。
Thus, the complex is high spin if  is less than the P, the weak field complex,  < P, 弱场配合物, 高自旋配合物, and the complex is low spin if  is greater than the P, the strong field complex.  > P, 强场配合物, 低自旋配合物
Crystal Field Stabilization Energy 晶体场稳定化能(CFSE)
CFSEs of Complexes配合物的晶体场稳定化能
Magnetic Moments of Complexes配合物的磁距
Molecules such as O2 and ions [Fe(H2O)6]2+ that contain unpaired electrons are paramagnetic 顺磁性. Whereas compounds having no unpaired electrons are diamagnetic 逆磁性. 拥有未成对电子的分子是顺磁性分子；分子中若没有未成对电子，称为逆磁性分子。
The size of the magnetic moment of a system containing unpaired electrons is related directly to the number of such electrons. 分子磁距的大小与未成对电子数成正比。
Paramagnetic and Diamagnetic 顺磁性和逆磁性
How to Use Crystal Field theory?
The color of complexes配合物的颜色
Enthalpies change of hydration for M2+ ions, in kJmol1. 二价金属离子的水合能
Color of Complexes
Complementary Color Theory颜色互补理论
When an object absorbs some component color light of sunlight, we see the complementary colors 互补色 of the object. 物体吸收太阳光中的某一组分光后，其颜色与吸收的组分光成互补关系。
For example, the blue color of the [Cu(NH3)4]2+ ion results because this ion absorbs orange and red light, leaving the complementary colors of blue. 如[Cu(NH3)4]2+离子吸收橙红色后，显橙红色的互补色——蓝色。
Color Circle
Enthalpies of Hydration for M2+ Ions金属离子的水合能
Hydrated transition ions
Coordination Equilibrium配离子的配合平衡
Formation constant and disassociation constant稳定常数和不稳定常数
Calculations |
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IP卡
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提升卡
置顶卡
沉默卡
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