Using Kröger-Vink notation eradicates many other conceptual reaction possibilities as a result of necessity of both cost and site stability. What's most unconventional is this first charge transfer band of Ni3+ peaks is at 400 nm, providing major absorption from four hundred to 480 nm and thus strong yellow coloration. https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share