Alfacite Energy Phenomenon was a term devised by Lieutenant Commander Spock in the mid-2260s, after publishing scientific papers on the "hybrid twinning" effect caused by Alfacite ore when the ore reacted with the USS Enterprise's transporter and duplicated Captain James T. Kirk.
Dr. Albar Exar used Spock's research on the Alfacite Energy Phenomenon to further his research and create a genetic duplicator that would allow him to save his hybrid son's life by dividing him into two distinct beings. (TOS - The New Voyages short story: "Ni Var")