Eureka!

How to Grow A Big, Beautiful Crystal

Crystal.

By Charlotte Hsu

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Jason Benedict, Assistant Professor, Department of Chemistry.

Jason Benedict, Assistant Professor, Department of Chemistry.

No, this isn’t “Breaking Bad,” but it does have some of the elements of the hit TV show: A chemistry teacher. Disciples ready to learn. And, of course, crystals.

This past fall, in conjunction with the International Year of Crystallography, UB chemist Jason Benedict organized the first-ever U.S. Crystal Growing Competition. In mid-December, five UB faculty members judged a total of 68 entries, mailed to Benedict’s lab by K-12 students and teachers from around the country.

Benedict’s research focuses on sponge-like crystals called MOFs (metal-organic frameworks) that could one day be used to mop up toxins or deliver drugs to tumors. He dreamed up the contest as a way to get children interested in the science of crystallography, which underlies the development of everything from drugs to airplane parts.

It seems the strategy worked. In the words of sixth-grader Renee Aga of Amherst, N.Y.—winner of “Best Overall Crystal” in the K-8 category—“It was just cool.”

All of these crystals were grown by Benedict or researchers in his lab as part of a trial competition:

Little Beauty

Because it’s easy to grow a perfect crystal that’s very small, Benedict created the “Jose Rule,” named for a member of his lab who submitted a teeny tiny crystal in a trial contest. “I think I even lost his crystal, it was so small,” Benedict recalls. According to the Jose Rule, entries had to weigh at least half a gram.

Too Many, Too Mini

One problem with growing a crystal too fast is that multiple miniscule crystals can emerge as the water rapidly vanishes.

Cloudy Chaos

Crystals grow as bits of alum gather on a central seed. The process isn't clean: If you could view it with a microscope, you'd see alum particles adhering to the seed, then falling off and reattaching. Slow growth enables orderly assembly. Fast growth breeds occlusions, which appear when particles attach at the wrong spot and can't unhitch before others pile on.

Like Rock Candy, In a Bad Way

“This is just a mess,” Benedict says. The rough, junky edges hint at a hectic history, in which individual units of alum surfaced too fast to gather in a regular pattern.

Ding, Ding, Ding!

Or maybe we should say, “Bling, bling, bling!” This big fellow is a winner: It’s clear and reflects light beautifully. It also has the right shape: eight primary sides, all glossy.