A Lifetime of Crystallography

Chemist Dick Marsh, a Techer through and through, has witnessed the evolution of X-ray crystallography (see "X-Ray Vision") since the era of Linus Pauling.

He studied applied chemistry at Caltech, receiving his undergraduate degree in 1943. He then joined the Navy, where his job was to degauss ships so they wouldn’t trigger magnetic mines.

After the war, he enrolled in graduate school at Tulane University, but when he tried to sign up, most of the classes were already filled. The registrar found one available class—at Sophie Newcomb College, the women’s college next door. The class was on X-ray crystallography, the study of crystals and their structure using X-ray diffraction.

As he wrote later in an essay for the American Crystallographic Association, he had never heard of X-ray crystallography. But the class changed his life, as he credits his instructor, Rose Mooney, for inspiring him to become a crystallographer.

(As a side note, according to Marsh’s essay, Mooney had been accepted to Caltech’s graduate program a few years prior. She didn’t know Caltech didn’t allow women at the time and the university didn’t know “R.C.L. Mooney” was a woman. Marsh wrote that Linus Pauling would help arrange a research assistantship for her and help transfer her to the University of Chicago, where she got her PhD.)

Marsh later transferred to UCLA for his PhD and returned to Caltech as a postdoc in 1950, focusing on the structures of smaller molecules. It was the heyday of structural chemistry. People from all over the world were flocking to Pasadena to work with Pauling, Marsh says.

Dick Marsh and Linus Pauling at Pauling’s 85th birthday celebration.

The first paper he published at Caltech was with Pauling, in which they used crystallography to find the structure of a molecule called chlorine hydrate. Pauling was extremely cogent and articulate, Marsh recalls. After solving a molecular structure, Marsh would show the results to Pauling, who would take a look and speak into a recording device, dictating an entire paper from start to finish for his secretary to type out.

Through his more than six-decade career at Caltech, Marsh has seen how computers have revolutionized the field. “When I started, I had a slide rule and a pencil,” he says. Now, in his role as senior research associate in chemistry, emeritus, he still goes to work every day. Solving chemical structures is a great puzzle, he says, and it’s the joy of cracking these riddles that keeps him going. Asked if he has any favorite discoveries after all these years, he can’t choose. “They’ve all been fun,” he says.

—Marcus Woo

Photos courtesy of the American Crystallographic Association