The works of the multidisciplinary artist László Moholy-Nagy—who believed in the power of art as a vehicle for social transformation and in the interrelatedness of art, life, and technology—are well represented within the Solomon R. Guggenheim Museum’s permanent collection. The museum’s founding director, German-born artist Hilla Rebay, acquired a large number of important art objects by Moholy-Nagy for the institution over the years: as early as 1929, Rebay began to purchase Moholy-Nagy’s work for Solomon Guggenheim’s budding collection of abstract and non-objective art, thus beginning a rewarding relationship between artist and patron, as paintings, works on paper and sculpture spanning virtually his whole career steadily entered the collection. From 1939 onwards, when the Museum of Non-Objective Painting (the forerunner of the Guggenheim) first opened in rented galleries in midtown Manhattan, Moholy-Nagy’s work was exhibited regularly in numerous solo and group presentations, maintaining a place of honor there.
   The artist’s masterful work A II (Construction A II) (1924) came into the Guggenheim’s collection in 1943 shortly after it had been exhibited in a group exhibition at the Museum of Non-Objective Painting. Moholy-Nagy created the painting soon after joining the faculty of the Bauhaus school of art and design in Weimar, Germany, founded by architect Walter Gropius. As if constructed around a mathematical formula, the painting is composed of two similar bodies of seemingly intersecting rectilinear planes and circles. A smaller, similar structure hovers below a larger one, both crossing through a white plane, against a bare ground of unprimed canvas. Varying in degrees of perceived transparency and color intensity, these shapes suggest movement and appear to overlap, while forming a novel architectural construction in space; they are illustrative of the Constructivist emphasis on simple geometric forms and theories of early 20th–century modern glass architecture.
   Moholy-Nagy made a series of small black-and-white woodcuts or linocuts of this same composition, whereby the printing process transformed the painting composition into its mirror image, elucidating the artist’s ongoing preoccupation with rendering the same composition or motif across mediums. One such work, Composition (Variant on A II) (ca. 1924), a print from the Hilla von Rebay Foundation on extended loan to the Guggenheim, is presented in the Guggenheim’s current exhibition,Moholy-Nagy: Future Present.
   As early as 1922, Moholy-Nagy began to make metal sculpture. He believed that new materials called for a new kind of art, and metal was appealing for its specifically modern nature and its connection to machinery and industry. He continued to work with metal until the end of his life in 1946, using the material for objects such as the Collection pieceDual Form with Chromium Rods (1946), a spiraling sculpture of intertwining rods perforating a thick slab of clear Plexiglas which was purchased from the artist’s widow in 1948. In Moholy-Nagy: Future Present, the sculpture hangs below the museum’s oculus over the fountain, where it presents an embodiment of the artist’s preoccupation with light—his favorite medium of expression, motion, and transparency. The mobile rotates gently in space, creating what Moholy-Nagy termed “vision in motion,” and casts a spectacular show of shadows against the wall.
László Moholy-Nagy, CPL 4, 1941. Oil and incised lines on Plexiglas, in original frame, 24 x 36 inches (61 x 91.4 cm); framed: 34 1/8 x 44 3/4 inches (86.7 x 113.7 cm)
  Moholy-Nagy was interested in newly manufactured materials, industrial supports, and commercial paints. In the mid-1920s, he began to work with plastics that typified industrial modernity, embarking on his experiments with the “curiosity of a scientist” (as Gropius put it). Around 1939, when he had settled in Chicago, Moholy-Nagy started working with Plexiglas. A plastic produced in sheets in the United States after 1934, Plexiglas was the artist’s favorite material to facilitate his exploration of light, and he used it until his death. The Guggenheim is particularly rich in its holdings of Moholy-Nagy’s Plexiglas works, best described as hybrids of painting and sculpture. The artist named them Space Modulators or gave them titles with letters that evoked his adopted home, as in CH 4 (1941), acquired from the artist’s estate in 1948; or he combined the first letter of the Windy City and the first two letters of the material, as in CPL 4 (1941)—another work from the Hilla von Rebay Foundation. These works consist of a flat sheet of Plexiglas that is meticulously incised and painted on both sides. The sheet is placed on parallel painted wood rails hanging a couple of inches from a backing board, forming a space that allows for a lively play of light and shadows that was particularly prized by the artist. In fact, Moholy-Nagy provided specific guidelines for the lighting of such works, in the ardent belief that light completed them.
  Other Plexiglas works include B-10 Space Modulator (1942), purchased in 1947 from Moholy-Nagy’s estate, an incised and painted sheet molded by the artist and attached to clips mounted a couple of inches from a backing board, also allowing for shadows to be cast in a dramatic display. The deliberate distortions of the material enhance the shadow effects and create a new space articulation for a constant “vision in motion.” Another type of Plexiglas work includes Space Modulator (1939–45), a piece in its original frame, which entered the collection in 1947. Here Moholy-Nagy has used an imperfect sheet of Plexiglas in which bubbles and defects have formed during the manufacturing process, but which the artist has used to his advantage. When lit in the manner that he stipulated, the flaws form beautiful patterns which play in dialogue with the colored shapes of the incised and painted composition. These “vehicles for choreographed luminosity” remain an integral part of Moholy-Nagy’s oeuvre and remind us constantly of his attraction to light in all its manifold iterations.

By Source:https://www.guggenheim.org/blogs/checklist/diverse-moholy-nagy-works-in-the-guggenheims-permanent-collection