1 / 54

Transition Metal Chemistry and Coordination Compounds

Transition Metal Chemistry and Coordination Compounds. 배위화합물의 화학. 전이금속의 성질 , 전자배치 , 산화상태 배위화합물 , 중심금속의 산화수 배위화합물의 기하구조 , 배위수 배위화합물의 결합 : 결정장이론 배위화합물의 반응 생체계의 배위화합물. The Transition Metals. Oxidation States of the 1 st Row Transition Metals

yahto
Download Presentation

Transition Metal Chemistry and Coordination Compounds

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Transition Metal Chemistry and Coordination Compounds

  2. 배위화합물의 화학 • 전이금속의 성질, 전자배치, 산화상태 • 배위화합물, 중심금속의 산화수 • 배위화합물의 기하구조, 배위수 • 배위화합물의 결합:결정장이론 • 배위화합물의 반응 • 생체계의 배위화합물

  3. The Transition Metals

  4. Oxidation States of the 1st Row Transition Metals (most stable oxidation numbers are shown in red)

  5. Ionization Energies for the 1st Row Transition Metals

  6. Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper

  7. N O - • • • • • • • • • • • • • • • • • • C O Cl H H H H H Coordination Compounds A coordination compound typically consists of a complex ion and a counter ion. A complex ion contains a central metal cation bonded to one or more molecules or ions. The molecules or ions that surround the metal in a complex ion are called ligands. A ligand has at least one unshared pair of valence electrons

  8. N O • • • • • • H H H H H Coordination Compounds The atom in a ligand that is bound directly to the metal atom is the donor atom. The number of donor atoms surrounding the central metal atom in a complex ion is the coordination number. Ligands with: one donor atom monodentate H2O, NH3, Cl- bidentate ethylenediamine two donor atoms three or more donor atoms polydentate EDTA

  9. bidentate ligand H2N CH2 CH2 NH2 • • • • Coordination Compounds polydentate ligand (EDTA) [Co(en)3]2+ Bidentate and polydentate ligands are called chelating agents

  10. ethylenediammine(en) acetylacetonate ion(acac) oxalate ion(ox) phenanthroline(phen)

  11. EDTA Complex of Lead

  12. OH- has charge of -1 K+ has charge of +1 ? Au + 1 + 4x(-1) = 0 NO3- has charge of -1 What are the oxidation numbers of the metals in K[Au(OH)4] and [Cr(NH3)6](NO3)3 ? Au = +3 NH3has no charge ? Cr + 6x(0) + 3x(-1) = 0 Cr = +3

  13. Naming Coordination Compounds • The cation is named before the anion. • Within a complex ion, the ligands are named first in alphabetical order and the metal atom is named last. • The names of anionic ligands end with the letter o. Neutral ligands are usually called by the name of the molecule. The exceptions are H2O (aquo), CO (carbonyl), and NH3 (ammine). • When several ligands of a particular kind are present, the Greek prefixes di-, tri-, tetra-, penta-, and hexa- are used to indicate the number. If the ligand contains a Greek prefix, use the prefixes bis, tris, and tetrakis to indicate the number. • The oxidation number of the metal is written in Roman numerals following the name of the metal. • If the complex is an anion, its name ends in –ate.

  14. Table 1. Names of Some Common Ligands in Coordination Compounds *In these ligands two forms are known; they differ in the atom that donates the electron pair to the metal ion.

  15. What is the systematic name of [Cr(H2O)4Cl2]Cl? tetraaquodichlorochromium(III) chloride ligands cation anion Write the formula of tris(ethylenediamine)cobalt(II) sulfate [Co(en)3]SO4

  16. Structure of Coordination Compounds Coordination number Structure 2 Linear Tetrahedral or Square planar 4 Octahedral 6

  17. Structure of Coordination Compounds Stereoisomers are compounds that are made up of the same types and numbers of atoms bonded together in the same sequence but with different spatial arrangements. Geometric isomers are stereoisomers that cannot be interconverted without breaking a chemical bond. trans-[Pt(NH3)2Cl2] cis-[Pt(NH3)2Cl2]

  18. trans cis Are these additional geometric isomers of [Co(NH3)4Cl2]? Structure of Coordination Compounds cis-[Co(NH3)4Cl2] trans-[Co(NH3)4Cl2]

  19. Structure of Coordination Compounds Optical isomers are nonsuperimposable mirror images. cis-[Co(en)2Cl2] trans-[Co(en)2Cl2] optical isomers not optical isomers chiral achiral

  20. Structure of Coordination Compounds Chiral molecules are optically active.

  21. Bonding in Coordination Compounds All equal in energy in the absence of ligands!

  22. Bonding in Oh Coordination Compounds Isolated transition metal atom Bonded Oh transition metal atom Crystal field splitting ( D) is the energy difference between two sets of d orbitals in a metal atom when ligands are present

  23. Oh Crystal Field

  24. Bonding in Oh Coordination Compounds DE = hn

  25. Absorbs blue, will appear orange. (6.63 x 10-34 J s) x (3.00 x 108 m s-1) D = hn = = 4.23 x 10-19 J 470 x 10-9 m hc D (kJ/mol) = 4.23 x 10-19 J/atom x 6.022 x 1023 atoms/mol = l = 255 kJ/mol The absorption maximum for the complex ion [Co(NH3)6]3+ occurs at 470 nm. What is the color of the complex and what is the crystal field splitting in kJ/mol?

  26. Strong field ligands Large D Weak field ligands Small D Bonding in Oh Coordination Compounds Spectrochemical Series I- < Br- < Cl- < OH- < F- < H2O < NH3 < en < CN- < CO I− < Br− < S2− < SCN− < Cl− < NO3− < N3− < F− < OH− < C2O42− ≈ H2O < NCS− < CH3CN < py (pyridine) < NH3 < en < bipy < phen) < NO2− < PPh3 < CN− ≈ CO

  27. Bonding in Oh Coordination Compounds

  28. Orbital Diagrams for High Spin and Low Spin Octahedral Complexes

  29. Bonding in Coordination Compounds

  30. Bonding in Coordination Compounds

  31. Bonding in Coordination Compounds

  32. 배위화합물의 반응 Ni2+ + 4CN- ⇄ [Ni(CN)4]2- Kf=1×1030 [Ni(CN)4]2- 는 열역학적으로 안정하다 [Ni(CN)4]2- + 4*CN- ⇄ [Ni(*CN)4]2- + 4CN- [Ni(CN)4]2-에서빠른 리간드 치환반응이 일어나므로 치환성착물(labile complex)이라고 한다. [Co(NH3)6]3+ + 6H+ + 6H2O ⇄ [Co(H2O)6]3+ + 6NH4+ Kf=1×1020 산성용액에서 [Co(NH3)6]3+는 열역학적으로 불안정하다 [Co(NH3)6]3+에서매우 느린 리간드 치환반응이 일어나므로 비활성착물(inert complex)이라고 한다.

  33. Chemistry In Action: Coordination Compounds in Living Systems

  34. Hemoglobin Figure from wiki

  35. Chemistry In Action: Cisplatin – The Anticancer Drug

  36. Ni(4s23d8) 사각 평면 구조인 [Ni(CN)4]2-이온은 반자성인 반면에 사면체 구조인 [NiCl4]2-이온은 상자성이다. 결정장 분리 도표로 설명하라 I- < Br- < Cl- < OH- < F- < H2O < NH3 < en < CN- < CO

  37. Cr(4s13d5) Ruby is colored by a small amount of chromium, Al2O3:Cr Cr6+ : orange Cr3+ : dark blue K2Cr2O7 Chromium(III) chloride (CrCl3) Chromium(III) chloride hexahydrate ([CrCl2(H2O)4]Cl·2H2O) pale green [CrCl(H2O)5]Cl2, and the violet [Cr(H2O)6]Cl3. Na2CrO4

  38. Cu(4s13d10) 짙은 청색과 녹색의 용액은 [Cu(H2O)6]2+와 [CuCl6]4-용액 중 하나이다. 용액의 색과 용액의 성분을 연결하고 그 이유를 설명하라 I- < Br- < Cl- < OH- < F- < H2O < NH3 < en < CN- < CO [Cu(NH3)6]2+는없고, 단지 [Cu(NH3)4(H2O)2]2+는 dark blue [Cu(H2O)6]2+ 는 pale blue [CuCl6]4- 는 노란색이나 가끔 녹색으로 보이는 것은 Cl-가모두 다 치환된 것이 아님.

  39. Mn(4s23d5) 수화된 Mn2+용액은 사실상 무색이다. 그 이유를 설명하라 I- < Br- < Cl- < OH- < F- < H2O < NH3 < en < CN- < CO

  40. 다음의 수화된 양이온 중에서 어느 것이 무색인가? 선택한 이유를 설명하라. Fe2+(aq), Zn2+(aq), Cu+(aq), Cu2+(aq), V5+(aq), Ca2+(aq), Co2+(aq), Sc3+(aq), Pb2+(aq)

  41. Fe(4s23d6) FeCl2와 FeCl3 이 들어 있는 용액 중 하나는 연노란색이고 하나는 갈색이다. 용액의 색과 성분을 연결하고 그 이유를 설명하라 FeCl2·4H2O FeCl2 light green to colorless FeCl3 orange/brown FeCl3·6H2O Sc3+ V5+ Zn2+: colorless

  42. Color of aquous solutions

  43. 배위화합물의 색 CrCl3∙6H2O

  44. Δ(cm-1(nm)) for octahedral complex

  45. Coordination isomers Isomers: CoClBr∙(NH3)5

  46. Linkage Isomers: [Co(NH3)5(NO2)]2+ pentaamminenitrocobalt(III) ion pentaamminenitritocobalt(III) ion linkage isomers : NO2, SCN-, OCN-

More Related