“No, Tsy isn’t authorized to just “print” money, the Federal Reserve Act gives that power to the Fed, However, the Coinage Act grants the Secretary of the Treasury rather broad coin seigniorage authority. Geithner could sidestep the debt ceiling this afternoon by ordering the West Point Mint to coin a 1 oz. $ 1 trillion coin. Tsy can then present the jumbo coins at the NY Fed to buy back $1 trillion in Fed-held debt (the Fed has to accept it, a creditor can’t refuse legal tender paid in to settle a debt):

(h) The coins issued under this title shall be legal tender… (k) The Secretary may mint and issue platinum bullion coins and proof platinum coins in accordance with such specifications, designs, varieties, quantities, denominations, and inscriptions as the Secretary, in the Secretary’s discretion, may prescribe from time to time.”