why d-d electronic transition occurs but p-p electronic transition not???????

Your question is valid but at wrong plateform. https://Shiksha.com will help you in answering questions which are related to education and career.You can post your above question on any site related to Physics or Eelctronics education or tutions.

Nrendra Singh, this is a totally technical question pertaining to a specific topic of a particular subjects. Such questions are generally not answered on this forum. Thbest way to find answers to such questions is through the net as rightly suggested by Vikas Naidu or though your college teachers.

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