How Can CN-, P(CH3)3, and SCN- Act as Both σ-Donors and π-Acceptors?

AI Thread Summary
CN-, P(CH3)3, and SCN- can act as both σ-donors and π-acceptors due to their possession of lone pair electrons and available π* orbitals. This dual behavior is explained by the concept of "pi-backbonding," where electron density is donated into antibonding orbitals. Such interactions are significant in catalysis, particularly in processes involving bond breaking. Understanding these ligand properties enhances insights into coordination chemistry. The discussion emphasizes the importance of these mechanisms in various chemical reactions.
ReidMerrill
Messages
65
Reaction score
2

Homework Statement


Describe, using sketches, how the following ligands can act as both σ-donors and π-acceptors:
CN-
P(CH3)3
SCN-

Homework Equations

The Attempt at a Solution



I suspect it has something to do with these ligands having lone pair electrons AND open π* orbitals.
How correct is this and if it is wrong then what is the explanation?
 
Physics news on Phys.org
ReidMerrill said:
I suspect it has something to do with these ligands having lone pair electrons AND open π* orbitals.
How correct is this and if it is wrong then what is the explanation?
This is basically correct. Look up "pi-backbonding" for a good explanation. Bonus fact: Electron backdonation into antibonding orbitals turns out to be really important in catalysis where bond breaking is important.
 
Thread 'Confusion regarding a chemical kinetics problem'

Thread 'Confusion regarding a chemical kinetics problem'

TL;DR Summary: cannot find out error in solution proposed. [![question with rate laws][1]][1] Now the rate law for the reaction (i.e reaction rate) can be written as: $$ R= k[N_2O_5] $$ my main question is, WHAT is this reaction equal to? what I mean here is, whether $$k[N_2O_5]= -d[N_2O_5]/dt$$ or is it $$k[N_2O_5]= -1/2 \frac{d}{dt} [N_2O_5] $$ ? The latter seems to be more apt, as the reaction rate must be -1/2 (disappearance rate of N2O5), which adheres to the stoichiometry of the...
View full post »

Similar threads

Schools How well does this course prepare me for college math?
Replies
10
Views
5K

Hot Threads

Recent Insights

Back
Top