Freed, a partner in Pei, Cobb, Freed & Partners, who was behind the US Holocaust Museum in Washington, died on Thursday in New York.
Most recently Freed had been worked on the US Air Force Memorial in Arlington, Virginia, now under construction, which has three stainless-steel spires more than 61m high.
Pei said that the Holocaust Memorial Museum was Freed's principal legacy. 'He felt it, he participated in it; he remembers his boyhood. Who else was better qualified to do it than Jim?'
Freed received a bachelor's degree in architecture in 1953 from Illinois Institute of Technology in Chicago, which was then under the direction of Mies van der Rohe. He worked briefly in the 1950s for Mies on the Seagram Building in Manhattan.
Freed joined the Illinois Institute of Technology between 1975 and 1978 as a dean of architecture. At that time, he was also part of a group of architects known as the Chicago Seven, which tried to challenge the prevalent Miesian orthodoxy at that time.