The Dream in the Machine

Rudolph Pariser uses one of the earliest computers to calculate the molecular structure of Dacron.

DuPont had a production problem in 1954: after creating an exciting new synthetic fiber called Dacron, researchers had no way to know ahead of time how well the fiber would take dye. Rudolph Pariser, a new member of the Jackson Laboratory team, with a background in analytical rather than organic chemistry, thought there might be a way around a lengthy and expensive series of trial-and-error experiments. He consulted with Robert Parr, one of his instructors at his alma mater, the University of Minnesota. Parr agreed that the emerging field of quantum chemistry might provide a quicker and more definitive answer to the Dacron problem.

The Dream in the Machine

1950s IBM computer

The IBM computer used by DuPont scientists in the 1950s filled an entire room.

Science History Institute

Since the 1920s scientists had known about molecular orbitals, which were used to describe the wavelike behavior of electrons in molecules. From these patterns Parr and Pariser believed that molecular structures and properties—including those of Dacron—could be predicted. But this couldn’t be done at a lab bench; since electrons move in the quantum world, their exact locations are a matter of probability—requiring calculations and plenty of them. The intensity and sophistication of the math required more than an adding machine. Computers were needed.

Fortunately DuPont was sufficiently committed to its new fiber to allow Pariser to travel to New York City, where he became one of the first chemists to train on the new IBM 701 computer, which was housed at IBM’s Madison Avenue facility. This room-sized marvel possessed the requisite computational power, and because it was not powered by vacuum tubes, there was less chance of a mid-computational failure—something that occurred all too often with earlier electronic brains. Pariser learned to create data-entry cards using a precise “language” expressed as sequences of rectangular holes punched into each card. Infinite patience was needed as thick decks of these punched cards were fed into the computer, a process that could take hours to complete. But in the end the 701 came through and provided the computational muscle that allowed the theoretical structures of Parr and Pariser to become a proven reality—and Dacron to become a leading fashion fiber.