charge transfer spectra
Charge transfer spectra:-
R.S muliken (Nobel's price -1966)
Electronic spectra which arieses to the electron transition which take place from to LUMO.
In some of molecule or complex the charge is transfer from one molecule to another molecule the phenomenon is known as charge transfer transition at the spectra transfer is known as charge transfer spectra.
This phenomenon is also known as donor -accepter concept.
The molecule which have high electronic density act as donor and the molecule which have low electron density act as acceptor.
The charge transfer spectra place from HOMO (donor) to LUMO (acceptor) which can be represented in given diagram.
The intensity of various bands absorve in charge transfer spectra depends energy on acceptor and donor.
If the energy difference between HOMO and LUMO is very high charge transfer.
In transition metal complexes charge transition spectra in two ways
1.MLCT (metal to ligand charge transfer)
2.LMCT (ligand to metal charge transfer)
1.LMCT :-
In transition metal complex if metal has vacant d-orbitals then can transfer it's electron two vacant orbital this of transition is known as LMCT and the spectra observed by this transition is known as LMCT spectra .
Kmo4,K2Cr2O7 in d-zero configuration but colour full due to charge transfer spectra.
In the given example metal is in higher oxidation state so there is no d- electrons
In this oxygen transfer electron to vacant d-orbitals of metals and charge transfer spectra is observed.
The transfer of charge can take place either in t2 and electron orbitals
2.MLCT :-
If metal ion transfer it's electron density (charge) to vacant pie anti bonding orbitals of ligand then this transition called MLCT, and observed spectra is known as MLCT spectra
This type of transition given by the complexes in which pie ligand are present.
R.S muliken (Nobel's price -1966)
Electronic spectra which arieses to the electron transition which take place from to LUMO.
In some of molecule or complex the charge is transfer from one molecule to another molecule the phenomenon is known as charge transfer transition at the spectra transfer is known as charge transfer spectra.
This phenomenon is also known as donor -accepter concept.
The molecule which have high electronic density act as donor and the molecule which have low electron density act as acceptor.
The charge transfer spectra place from HOMO (donor) to LUMO (acceptor) which can be represented in given diagram.
If the energy difference between HOMO and LUMO is very high charge transfer.
In transition metal complexes charge transition spectra in two ways
1.MLCT (metal to ligand charge transfer)
2.LMCT (ligand to metal charge transfer)
1.LMCT :-
In transition metal complex if metal has vacant d-orbitals then can transfer it's electron two vacant orbital this of transition is known as LMCT and the spectra observed by this transition is known as LMCT spectra .
In the given example metal is in higher oxidation state so there is no d- electrons
In this oxygen transfer electron to vacant d-orbitals of metals and charge transfer spectra is observed.
The transfer of charge can take place either in t2 and electron orbitals
2.MLCT :-
If metal ion transfer it's electron density (charge) to vacant pie anti bonding orbitals of ligand then this transition called MLCT, and observed spectra is known as MLCT spectra
This type of transition given by the complexes in which pie ligand are present.
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