The students hailing from Iran, Israel, Egypt, Saudi Arabia, the Palestinian Authority, Syria and Jordan had never met each other. They arrived at the workshop in Petra, Jordan, with only the scantest understanding of each other's cultures and lifestyles.

So while the reason for their January trip was a simple weeklong workshop on chemical bonding, the metaphor in the subject matter was not lost on anyone.

And that, said workshop architect Roald Hoffmann, was the point.

Hoffmann, Cornell's Frank H.T. Rhodes Professor of Humane Letters, is a 1981 Nobel laureate (with Kenichi Fukui) for his work explaining the course of chemical reactions. But this year, he and Pere Alemany, a University of Barcelona professor, under a Discovery Corps Senior Fellowship from the National Science Foundation, took on a challenge in human interactions: the task of coaxing bonds between young scientists from across the Middle East.

For security reasons, the workshop wasn't widely publicized. Everyone was only too aware of ongoing violence in the region. One Turkish student bowed out the day before the workshop, citing personal safety concerns. But the rest took the risks in stride.

Hoffmann's inspiration for the Petra workshop came from two conferences in Malta over the last three years, which brought together chemists from across the region to make connections and overcome political boundaries.

"I wanted to take the spirit of the Malta meetings to a different level," said Hoffmann. "I wanted to get younger people involved -- I had a dream of getting future leaders in chemistry together. And my second idea was, let's push things and move into the region, so as to get people used to working within the Middle East."

Hoffmann planned three workshops: the one in Petra, one slated for Egypt on nanochemistry later in the year and one in Qatar in 2007 on bioinorganic chemistry, all taught by leaders in the fields.

The students at Petra learned chemistry, certainly. But ask Hoffmann about the defining moments, and he remembers the human ones: the meal the students cooked together, for example, or the simple Arabic girls' game -- the group in a circle, dancing around a single person in the center -- they played while waiting for a bus.

"There was an extraordinary amount of talk about politics and religion," Hoffmann said. There was also music and the kind of friendship-building that happens after grueling days of shared work. Hoffmann and Alemany taught nine hours every day.

Back in Ithaca after the workshop, Hoffmann read the participants' anonymous evaluations.

"We could not have asked for more, and we are forever grateful," wrote one student. "I do sincerely hope that our paths will cross again soon."

"I think that special and strong friendships were made in the workshop," wrote another. "I felt that people really connected with each other, and it was interesting and beautiful to see."

Hoffmann wrote his own evaluation, of sorts:

"Atoms bond, or fail to do so, in very specific ways so as to make up those larger, useful molecules whose complexity ultimately allows the richness of life, the balance of risk and benefit that makes a molecule mean something to us. The attraction of the opposite charges overcomes the repulsion of the like ones. Atoms bond. They bond, sometimes sharing electrons, sometimes transferring them between each other. Inanimate, atoms have no option. Human beings have a choice."

He is grateful for the opportunity to watch his students make that choice.

"I wanted the bonding to take place," he said. "And it was wonderful and touching that it did."