The total number of valence electrons in $W(\eta^3-Cp)(\eta^5-Cp)(CO)_2$ is ______________.(Atomic number of W = 74)
Valence Electron Count for $W(\eta^3-Cp)(\eta^5-Cp)(CO)_2$
This solution determines the total number of valence electrons for the given Tungsten (W) complex using the electron counting method.
1. Valence Electrons of Tungsten (W)
Tungsten (W) is a Group 6 transition metal.
- Atomic Number (Z) = 74
- Electronic Configuration: $[Xe] 4f^{14} 5d^4 6s^2$
- Number of valence electrons contributed by W = 6 (from $5d^4$ and $6s^2$)
2. Electron Contribution of Ligands
The complex contains three types of ligands:
- $\eta^3$-Cyclopentadienyl ($\eta^3$-Cp): This ligand binds in an haptic 3 mode, donating 3 electrons.
- $\eta^5$-Cyclopentadienyl ($\eta^5$-Cp): This ligand binds in an haptic 5 mode, typically donating 5 electrons.
- Carbonyl (CO): Each CO ligand is a neutral ligand that donates 2 electrons. Since there are two CO ligands, their total contribution is $2 \times 2 = 4$ electrons.
3. Total Valence Electron Calculation
The total number of valence electrons is the sum of the valence electrons from the metal center and all the ligands.
Total Valence Electrons = (Valence e⁻ of W) + (e⁻ from $\eta^3$-Cp) + (e⁻ from $\eta^5$-Cp) + (e⁻ from 2 CO)
Calculation: $6 + 3 + 5 + (2 \times 2)$
Total Valence Electrons = $6 + 3 + 5 + 4 = 18$
Conclusion
The total number of valence electrons in the $W(\eta^3-Cp)(\eta^5-Cp)(CO)_2$ complex is 18.
Important Questions from 18 Electron Rule
The given zirconocene compound, $(\eta^5-\text{Cp})_2\text{ZrEt}_2$, when heated in the presence of an equimolar amount of $\text{PMe}_3$ results in the formation of a compound $X$ which obeys the 18 electron rule. The reaction also resulted in the release of a saturated hydrocarbon.
[Given: Atomic number of $\text{Zr} = 40$]
The structure of compound $X$ is ________
The number of metal-metal bond(s) in the complex $[(\eta^5-Cp)Mo(CO)_2]_2$ is $x$ and in $[(\eta^5-Cp)_2Fe_2(CO)_3]$ is $y$. The value of $x + y$ is ___________.
(Assume 18 electron rule is followed.)
(Answer in integer)$[CpMoCl_2]_2$ obeys the 18 electron rule. The correct structure of this compound is
(atomic number of Mo = 42)
- The species which follows 18-electron rule is
(en = ethylenediamine)
