The red color of oxyhaemoglobin is mainly due to the:a)d–d trans...
Each hemoglobin protein is made up subunits called hemes, which are what give blood its red color. More specifically, the hemes can bind iron molecules, and these iron molecules bind oxygen. The blood cells are red because of the interaction between iron and oxygen.
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The red color of oxyhaemoglobin is mainly due to the:a)d–d trans...
Explanation:
The red color of oxyhaemoglobin is mainly due to the intra-ligand * transition.
Intra-ligand * transition:
It is a type of electronic transition that occurs within the ligand molecule in coordination compounds. In oxyhaemoglobin, the ligand is the oxygen molecule (O2) which has a pair of electrons that can absorb light energy and undergo an electronic transition.
The electronic transition involves the promotion of an electron from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) within the ligand molecule.
In the case of oxyhaemoglobin, the electrons in the O2 molecule absorb light energy in the blue-green region of the spectrum and undergo an intra-ligand * transition to a higher energy level.
As a result of this transition, the O2 molecule becomes negatively charged and forms a complex with the iron atom in the haemoglobin molecule. This complex is called oxyhaemoglobin and it has a characteristic red color.
Conclusion:
Therefore, the red color of oxyhaemoglobin is mainly due to the intra-ligand * transition that occurs within the oxygen molecule in the haemoglobin complex.