Larkin hit a 3 and Miami was up 39-35 as part of eight consecutive scoring possessions for the Hurricanes.
Down 42-35, the Tar Heels answered with 3s from Paige and Hairston before Larkin's runner at the end of the half made it 44-41.
"I thought the first half was about as high a level of basketball as I've seen all year long," Larranaga said. "That's what I told the team at halftime. I said, 'We're playing great. They're playing great. This is a great game. We've got to keep playing great.' The guys did."
Miami's Durand Scott, who was the star with 32 points a day earlier in a semifinal against North Carolina State, left 26 seconds into the game clutching his back. He returned by the 13-minute mark of the half.
Scott scored on consecutive possessions as the Hurricanes closed within 18-17. He finished with six points and a spot on the all-tournament first team.
Fifteen of the game's 32 first-half field goals were 3-pointers.
Gamble, who's from Durham (about eight miles from North Carolina's campus in Chapel Hill), finished with game highs of 10 rebounds and three blocked shots.
Notes: Not only was it Miami's first ACC tournament title appearance, it was the Hurricanes' first conference tournament championship game in basketball in any league. ... Williams was denied his 700th career coaching victory. Williams is 699-179. ... North Carolina has won 90 games all-time in the ACC Tournament. Duke has the most with 91. ... North Carolina fell to 8-5 in ACC tournament finals in Greensboro. ... North Carolina will have to win its NCAA Tournament opener to notch its 34th 25-win season. ... Miami won both regular-season meetings -- 68-59 on Jan. 10 in Chapel Hill and 87-61 on Feb. 9 in Coral Gables, Fla.