The move is part of the restructuring plan hatched after RBS was bailed out by the government.
Aberdeen is taking over £13.5bn worth of assets and said it will issue new shares to raise cash to fund the deal.
A spokesman said there would be no job losses among the 65 staff.
Chief financial officer with RBS, Bruce Van Saun, said: "This transaction represents another step in our plan to restructure RBS around its core customer franchises."
Aberdeen also said it had entered into a distribution agreement with RBS Wealth Management for a minimum of five years.
Martin Gilbert, chief executive of Aberdeen Asset management, said: "Aberdeen has been looking for some time to establish a high quality platform in the alternatives arena, and this exactly fits our requirements.
"This is a well-run business with an excellent distribution network, which has delivered good performance over a number of years."