Also noted: Guitarist Johnny Smith, scientist Jerome Karle

Johnny Smith, 90, a jazz guitarist whose luscious tone, understated versatility and exemplary swinging style brought him a half-century of acclaim and whose ­composition "Walk, Don't Run" became a surf-rock hit for the Ventures in the 1960s, died June 11 at his home in Colorado Springs, Colo.

The cause was complications from a fall, said his son John Smith III.

He accompanied Benny Goodman, Stan Getz, Bing Crosby, Beverly Kenney and Hank Jones, among others, during his career. A hallmark of Smith's playing was an intricate but seemingly effortless approach to jazz and bossa nova standards.

"He took very logical solos, like someone had written them all out ahead of time, but that was not the case," said Vincent Pelote, acting director of the Institute of Jazz Studies at Rutgers University. "That's how organized a mind he had, and he had the technical ability to pull it all off. And that's what floored a lot of musicians, too."

Smith, who had a Depression-era upbringing first in Alabama and then in Maine, was largely self-taught as a guitarist and worked his way into the top ranks of New York's music scene. He played on the radio with the NBC studio orchestra, led by conductor Arturo Toscanini.

His most enduring composition was the jaunty "Walk, Don't Run," recorded by Smith in the mid-1950s and later covered by guitarist Chet Atkins. The Atkins version inspired the Ventures, whose interpretation became a pop hit in the early 1960s.

Jerome Karle, 94, a U.S. Naval Research Laboratory scientist who shared the Nobel Prize in chemistry for discovering a way to determine the structure of molecules, a breakthrough that made possible significant advances in medicine and other fields of science, died June 6 at the Leewood Healthcare Center in Annandale, Va.

Karle was a scientific polyglot, schooled in biology and chemistry but proficient as well in physics and mathematics. He shared the 1985 Nobel Prize in chemistry with the late Herbert Hauptman, a mathematician with whom he pursued his pioneering research in the 1950s and '60s at the Naval Research Laboratory in Washington.

The two men and their colleagues — including Karle's wife, Isabella Karle, a Naval lab chemist — took on a problem that had vexed scientists for years: the challenge of discerning the structure of three-dimensional molecules, combinations of atoms that were the simplest units of chemical compounds. They were too small for the most powerful of optical microscopes.