To the frustration of many art museum visitors, well-known abstract expressionist painters like Jackson Pollock and Mark Rothko weren’t always keen on explaining their non-representational work, leaving viewers to puzzle out the meaning behind “No. 5” and “No. 61 (Rust and Blue)” for themselves. Their contemporary, Robert Motherwell, however, left behind a trove of materials that offer some insight into the artist’s mind and process. From catalogs for his early exhibitions at Peggy Guggenheim’s Art of This Century gallery to correspondence with fellow artists and critics, many items related to Motherwell’s work will be on view at the Donald W. Reynolds Center for American Art and Portraiture as part of an exhibition sponsored by the Archives of American Art. Presented to commemorate the 100th anniversary of Motherwell’s birth, the small show explores the creation of his famous “Elegy to the Spanish Republic” series and his intricate collages. Unfortunately, visitors won’t be able to compare the artist’s sketches to his completed work: None of the American Art Museum’s works by Motherwell are currently on display. The exhibition is on view daily 11:30 a.m. to 7 p.m. at the Donald W. Reynolds Center for American Art and Portraiture, 8th and F Streets NW. Free. (202) 399-5015.