Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 4
Communication Breakdown; Confusion; Time Pressure
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Procedure
I had just taken over as [Sector] Controller 2 minutes prior to this event. Aircraft X was talking to ZZZ Approach on the ZZZZZ arrival. The previous [Sector] Controller had coordinated this aircraft stopped at 14;000 due to another emergency aircraft he had worked earlier. ZZZZZ aircraft; by procedure are already issued an OPD (Optimal Profile Descent) except maintain 14;000. Aircraft Y was descending via the ZZZZZ1 arrival. The aircraft neared the ZZZ approach boundary and I had to call Approach for a hand off. The Controller asked if Aircraft Y was descending OPD  to which I replied yes and asked if the aircraft was radar contact. She replied no because the aircraft was not separated from Aircraft X. These aircraft are procedurally separated. I was forced to turn Aircraft Y but as I issued the turn away from approach; the Controller accepted the hand off. As a result of this I violated ZZZ approaches airspace without a hand off. I expedited Aircraft Y to 11;000 and shipped the aircraft to ZZZ Approach. The CIC spoke to the ZZZ Approach Supervisor who stated the Controller was new to the procedures. I don't believe this alleviates the need to know basic procedures of separation before plugging in and controlling traffic. The ZZZ Controller created an unsafe situation for no reason by forcing me to turn out Aircraft Y.The procedures work fine as long as the Controller knows how to use them.
Center Controller reported an airspace deviation associated with a procedure that the receiving Controller may not have been understood.