USC chemistry professor Arieh Warshel gets a congratulatory kiss from… (Nick Ut / Associated Press )
As a chemistry professor at USC, Arieh Warshel says he sometimes finds it difficult to convince his fellow scientists that computers have a place in experimental fields like his own.
Many people, he laments, use them to make or watch movies, "but not to understand."
Though Warshel may hold a minority view on a campus with strong ties to Hollywood — visitors to his laboratory's website are informed that his animated computer simulations are not available on Netflix — he got a huge endorsement Wednesday from the Royal Swedish Academy of Sciences in the form of a Nobel Prize.
Warshel, Michael Levitt of Stanford University and Martin Karplus of Harvard University were awarded the 2013 Nobel Prize in chemistry for their pioneering use of computer modeling programs to help predict and illustrate complex chemical reactions.
The longtime collaborators and close friends will share about $1.2 million in prize money for devising programs that blend elements of classical chemistry with the strange and dualistic realm of quantum physics.
Their work, which began in the 1970s, has revolutionized chemistry and biochemistry research to the point that some scientists now conduct as much of their work on computers as they do in the lab with beakers and test tubes.
Though much of this change has occurred outside the public eye, members of the academy said it had led to a deeper understanding of molecules essential for life, as well as those used for pharmaceuticals, energy production and other industrial purposes.
"Chemical reactions occur at lightning speed," the academy said in its announcement. "In a fraction of a millisecond, electrons jump from one atomic nucleus to the other. Classical chemistry has a hard time keeping up. … Aided by the methods now awarded with the Nobel Prize in chemistry, scientists let computers unveil chemical processes."
At Stanford, Levitt said he was thrilled to see that the contribution of computers to chemistry and biology research was finally being recognized. He said the approach he has championed for about 40 years was just now coming into its own.
"As somebody who never really worked in a lab, it's very nice to see that computers have this place to play," he said.
Levitt, 66, drew a parallel with the aircraft industry.
"Thirty or 40 years ago, airliners were designed by engineers in wind tunnels. Now it's all done by computer," Levitt said. "I think we're going to get that way in biology and chemistry."
At his home in Cambridge, Mass., Karplus told a Harvard Gazette reporter that well-wishers had been asking him to explain his work in "simple terms."
"If you like how a machine works, you take it apart," said the 83-year-old Vienna native, who also has an appointment at the University of Strasbourg in France. "We do that for molecules."
In the 1970s, chemists relied on three-dimensional models of molecules — Tinker Toy-looking assemblies of sticks and balls — and X-ray crystallography to divine the shape of molecules and study their interactions.
Even when scientists began using computer programs in the 1970s, limits in processing power forced them to focus on small molecules. They also had to choose between using classical or quantum theories of physics.
To address these problems, the three chemists came up with computer modeling programs that were able to use both. By applying quantum calculations to the most chemically active portions of interacting molecules, and classical equations to less dynamic areas, they were able to calculate plausible reactions that could then be tested in actual experiments.
Their methods are currently being used to optimize the efficiency of solar cells and improve catalysts that "clean" the exhaust fumes of motor vehicles. Warshel made particular mention of the fact that computers can help pharmaceutical researchers find ways to "outsmart" a virus, such as HIV, that mutates in response to a drug treatment.
Much of the prize winners' early work was conducted in Israel, where Warshel and Karplus worked together on a powerful computer called Golem. The device was named after a creature in Jewish folklore who is brought to life from mud.
Warshel, who, like Levitt, has U.S. and Israeli citizenship, said one of the first congratulatory phone calls he received Wednesday was from Israeli Prime Minister Benjamin Netanyahu.
Warshel, 72, said the prime minister did not understand the nature of the professor's work, but after a one-minute explanation he came to recognize its significance.
"Netanyahu told me that from now on he was going to force all his ministers to say whatever it was they wanted to tell him in just one minute," Warshel said, eliciting laughter from a crowd gathered at USC's Town and Gown Ballroom.
Meanwhile, theoretical chemists across the globe were basking in the new recognition of in silico, or computer simulated, research.
"I'm super excited," said James Skinner, a theoretical chemist at the University of Wisconsin-Madison. "Chemistry is basically an experimental field, and I think experimentalists sometimes were just skeptical that theorists could make a contribution."
Computer analysis is particularly helpful in studying large protein molecules, which consist of tens of thousands of atoms. John Straub, a computational chemist at Boston University, said that only with a computer could researchers create a model "that has a remarkable level of detail that can't really be captured by theory or experiment."
Asked what made him persevere for decades, even when his field received little recognition, Warshel shrugged.
"I had nothing else to do," he said.
Times staff writers Amina Khan and Geoffrey Mohan contributed to this report.