SMA ON IFR DEP HAS CLOSE CALL WITH DESCENDING ACR-MLG NEAR RDU ARPT. LESS THAN STANDARD SEPARATION.

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WE HAD LIFTED OFF RWY 5L (USED FULL LENGTH) AT XA53 EDT; MADE LEFT TURN TO HDG 350 DEGS AFTER REACHING DEP END OF RWY 5L; CLBING AT 500 FPM. SWITCHED TO ASSIGNED DEP CTL FREQ 132.35 WHEN INSTRUCTED; CALLED IN AND RECEIVED ACKNOWLEDGEMENT AND RADAR CONTACT VERIFICATION ON SQUAWK CODE XXXX. MY WIFE IN RIGHT SEAT; WHO HAS MORE THAN 1000 HRS AS A PAX WITH ME; SAID 'SEE THAT?' ALMOST SIMULTANEOUSLY I OBSERVED WHAT I BELIEVE WAS AN MLG AT 2 O'CLOCK; BUT IT MAY HAVE BEEN AN MLG IN A SHALLOW DSNDING TURN TO THE LEFT AT WHAT I JUDGED 1/2 MI AND NOT MORE THAN 500' ABOVE ME. AS HE CROSSED 500-700' IN FRONT OF ME AND PERHAPS 300' ABOVE ME; I COULD EASILY READ THE COMPANY INSIGNIA ON THE ACFT. AS THE ACFT PASSED TO MY LEFT IT CONTINUED A SHALLOW DSCNT AS I WAS CONTINUING MY 500 FPM CLB TO 2000'. FLT CONDITIONS WERE SCATTERED CUMULUS ABOVE 3000'; VIS 3-4 MI IN HAZE WHICH EXTENDED UP TO 8000-9000'. NO CALL WAS MADE TO ME RE: THE TFC. AFTER A FEW SECS I CALLED THE CTLR ON 132.35 AND ASKED; 'DID YOU SEE THE TFC THAT JUST PASSED IN FRONT OF ME?'; OR WORDS TO THAT EFFECT. AFTER A MOMENTARY PAUSE THE REPLY WAS; 'I SAW HIM;' OR WORDS TO THAT EFFECT. ON REACHING 2000' DEP CTL INSTRUCTED TURN LEFT TO 030 DEGS AND CLB TO 3000'. THEN LATER PROCEED DIRECTLY TO LVL WHEN RECEIVING AND CLB AND MAINTAIN 7000'. NO OTHER COM UNTIL HANDED OFF TO ZDC ON 132.02.