9.6: Chapter 6

Last updated
Save as PDF

Page ID: 126695

Taro Saito
Kanagawa University

\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

6.1

Oxide ions are weak-field ligands and transition metal ions assume high-spin states. Fe³⁺ ions have d⁵ electron configurations and the LFSE is zero either in the octahedral or in tetrahedral coordination. On the other hand, F²⁺ ions tend to enter octahedral holes, because the LFSE for the octahedral coordination by six oxide ligands is larger than the one for tetrahedral coordination by four oxide ligands. This is one of the reasons why magnetite Fe3O4 has an inverse spinel structure B³⁺[A²⁺B³⁺]O₄.

6.2

\[trans-[PtCl_{2}(PEt_{3})_{2}] + EtMgBr \rightarrow trans-[PtCl(Et)(PEt_{3})_{2}] + MgBrCl \nonumber \]

6.3

CpV(CO)₄
[CpFe(CO)₂]₂

6.4

The trans effect of Cl^- is larger than that of NH₃. Therefore, it is possible to synthesize geometrical isomers selectively by choosing starting compounds.

\[[Pt(NH_{3})_{4}]^{2+} + 2 Cl^{-} \rightarrow trans-[PtCl_{2}(NH_{3})_{2}] \nonumber \]

\[[PtCl_{4}]^{2-} + 2 NH_{3} \rightarrow cis-[PtCl_{2}(PEt_{3})_{2}] \nonumber \]

6.5

Unless [Cr³⁶Cl(NH₃)₅]²⁺ forms by the addition of an isotope ion ³⁶Cl to the aqueous solution of the reaction \[[CoCl(NH_{3})_{5}]^{2+} + [Cr(OH_{2})_{6}]^{2+} \rightarrow [Co(OH_{2})(NH_{3})_{5}]^{+} + [CrCl(OH_{2})_{5}]^{2+},\[it is concluded that the chloride ion coordinated to cobalt transfers to chromium by the inner-sphere mechanism via a bridged structure [(NH₃)5-Co-Cl-Cr(OH₂)₅]⁴⁺.