The Big Chill
A Visit to the Coldest Place in Town
This summer, on those days when the air feels like a wet cat-fur plaster on your skin, think of a cluttered, fluorescent-lit storeroom in the basement of the Smith Building on the campus of Towson University. It's almost always cooler in the basement of any building, but in a very tiny, tightly controlled space in this basement, cool is taken to the penultimate extreme: minus 452 degrees Fahrenheit, or 4 degrees Kelvin above absolute zero, the theoretical point at which all molecular activity ceases, the absolute lowest possible temperature.
The storeroom-cum-lab is the domain of Lev Ryzhkov, associate professor of chemistry at Towson. For more than a decade, the 37-year-old Ryzhkov has been examining the molecular structure of biradicals, or molecules the structures of which include two unpaired electrons. "[They] are so fragile that they don't live long," Ryzhkov explains in an accent still redolent of his native Ukraine. "They tend to fall apart into fragments, or they tend to react to other molecules at a very rapid pace. And when I say rapid, I mean literally nanoseconds."
To study biradical structure, Ryzhkov says, you must either make instruments fast and sensitive enough to gather information about a whizzing, short-lived molecule on the fly--currently a very expensive and technically involved proposition that produces somewhat limited data--or you must fix a molecule in place and slow its reactivity long enough to be able to get a good look. Ryzhkov and his colleagues and students do this by generating the experimental materials inside of a lab-grown crystal, chilling the crystal to 4 degrees Kelvin with the use of liquid helium, illuminating the crystal sample with ultraviolet radiation to slow down molecular activity, and examining the "frozen" molecule with a device called an electron paramagnetic resonance spectroscope.
In his basement lab, the shaven-headed, black-clad Ryzhkov offers a cook's tour of his apparatus. He shows off the enormous spectrometer electromagnets, two olive-drab discs the size of medieval siege-engine wheels, sitting upright on their edges. He explains the elaborate and precise system that pumps and regulates the flow of liquid helium from its pressurized Dewar vessel (essentially a large thermos bottle full of supercold gas, rented from regional suppliers for around $200 per day's worth of juice) into a small device between the two magnets that looks something like an elegant bedside lamp. The "bulb" of the lamp, a thin, clear quartz tube about the size of an unfiltered cigarette, holds Ryzhkov's crystal sample. When emptied of air and filled with liquid helium, the sample tube drops to more than 500 degrees Fahrenheit below room temperature. (The rest of the basement lab experiences almost no chill.) The overall area reduced to that temperature is only 1 or 2 cubic centimeters, but it is the coldest 1 or 2 cubic centimeters for many miles around.
Once the molecule he's studying is on ice, so to speak, Ryzhkov can examine the sample at his leisure. He can even rotate the sample to get a more complete view of the molecule in question, while the spectrometer feeds data on its structure and composition into an ordinary-looking Macintosh computer on a nearby desk. (See Research : Diazenyl and other Biradicals for a more complete summary of Ryzhkov's research than an English major who dropped Chemistry 101 after five days could ever hope to offer.) Ryzhkov seems very fond of his hodgepodge of equipment, especially his 1970s-vintage spectrometer. "It's a damn good one," he asserts. "They don't make magnets nowadays like they used to."
Asked to imagine a room the size of his computer-crammed office--pleasantly temperate on an unseasonable 80-degree April day--chilled to 472 below, Ryzhkov nods. "It's very difficult to imagine from a human perspective," he says. "No living organism can be 'living' in such an environment. Essentially, everything [would] freeze instantaneously or very quickly." (By comparison, biological materials--sperm, eggs, embryos, etc.--are frozen for long-term viable storage using liquid nitrogen at a relatively balmy 77 degrees Kelvin, or minus 321 degrees Fahrenheit.)
Ryzhkov points out that the cold his experiments require is akin to that of interstellar space: "All you have to do is be on the dark side of the moon or the Earth, have no solar radiation either reflected or direct on you, pop the spacecraft [hatch], and voila--4 K." He adds with a shrug, "The vacuum would kill you first. I don't think you would notice that you're getting cold."
Liquid helium's extreme low temperature makes it a useful and fairly common research tool; hospitals use it to cool the megamagnets in magnetic-resonance-imaging (MRI) equipment. Physicists and scientists doing superconductor research work at temperatures even closer to the inviolate threshold of absolute zero, but Ryzhkov says that getting below the 4 K temperature liquid helium provides "is not very easy. . . . It becomes fairly complicated fairly quickly."
Ryzhkov emigrated to the United States from the former Soviet Union in 1980, earning his Ph.D. from Brown University and doing postdoctoral research at Yale before coming to Towson in 1995. Asked about his own tolerance for cold, he effuses, "I enjoy cold weather tremendously. I couldn't possibly live in California without change of season--I need to inhale the crisp, icy air at least four months a year."
Baltimore summers? "I can do without them," he says with a noticeable chill. "I just refrigerate myself with the air conditioner in my room."
Asked about the legendarily brutal winters of his native land, the professor protests, "The winters in Ukraine are not that bad. The reason they are 'bad' is that the infrastructure to resist them is bad," he says. "When Napoleon came over [in 1812], on the same winter day in France, his troops would have moved easily because there were roads that would not turn into frozen pools of death. But in Russia you are exposed to the elements to such an extent that, once the winter comes, you'd better be very well prepared. As long as you have what you need, it's not all that bad."
In the long term, Ryzhkov and his associates hope to unlock a few of the remaining secrets of molecular inner workings and provide increased control over chemical reactions in a solid state. "It is possible that you can take one crystal and, upon irradiation, transform it into another crystal," he says. "The crystal structure rearranges literally in front of your very eyes!" But as the spring semester winds down and the summer months loom ahead, it sounds as though his adventures near the coldest cold possible under the laws of the universe aren't lost to him amid the incoming data.
"When you put your hands in that area [near the sample], you begin to understand more perfectly what this cold is all about," he says with a smile. "To hear how the metal components sing as you open the helium, how things begin to expand and contract and emit sounds--high-pitched noise, low-pitched, even crackling--it's a big part of the experience."
Sizzlin' Summer (5/19/2010)
Our annual comprehensive guide to surviving, thriving, and diverting yourself until September
The Scenic Route (5/19/2010)
Rediscovering the countryside from a skinny-ass bike seat
Parks and Rec (5/19/2010)
The Lady Vanishes (8/4/2010)
Meet Henrietta Vinton Davis-one of the most amazing women you've probably never heard of
Blaster Master (7/14/2010)
Landis Expandis can't live without his radios
The Black Box (6/16/2010)
Baltimore's African-American indie filmmakers search for an audience
812 Park Ave.
Baltimore, MD 21201