Narrative:

I was working sector X and had given an E120 the restriction to cross zzzzz intersection at 140. Sector Y called me and told me that a C172 wanted the RNAV approach to the airport and that he was my control. By the time the E120 was over zzzzz; sector Y had taken the hand off and I had transferred communications of the E120. Sector Y has control for descent but since the C172 was over a nearby fix at the time I knew that they were responsible for separating the two aircraft in their sector. When I noticed the E120 [was] descending and converging with the C172; I initiated a call to sector Y. After 3 attempts; sector Y answered and I asked them if it was their intention to descend the E120 below the C172. I had already issued an approach clearance to the C172. The sector Y controller said he would turn the E120. The E120 was turned behind the C172 and I issued traffic to the C172. The closest proximity appeared to be 2.6 miles and 500 ft. I believe that the sector Y controller was not aware that control of the C172 was given to sector 7 and did not know that the C172 was not flying on the flight plan route. Communication needed to be better.

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Original NASA ASRS Text

Title: Enroute Controller described a loss of separation event apparently a result of confused and incomplete coordination between sectors.

Narrative: I was working Sector X and had given an E120 the restriction to cross ZZZZZ Intersection at 140. Sector Y called me and told me that a C172 wanted the RNAV approach to the airport and that he was my control. By the time the E120 was over ZZZZZ; Sector Y had taken the hand off and I had transferred communications of the E120. Sector Y has control for descent but since the C172 was over a nearby fix at the time I knew that they were responsible for separating the two aircraft in their sector. When I noticed the E120 [was] descending and converging with the C172; I initiated a call to Sector Y. After 3 attempts; Sector Y answered and I asked them if it was their intention to descend the E120 below the C172. I had already issued an approach clearance to the C172. The Sector Y Controller said he would turn the E120. The E120 was turned behind the C172 and I issued traffic to the C172. The closest proximity appeared to be 2.6 miles and 500 FT. I believe that the Sector Y Controller was not aware that control of the C172 was given to Sector 7 and did not know that the C172 was not flying on the flight plan route. Communication needed to be better.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.