Two of The Florida State University's
most accomplished scientists recently joined forces on a collaborative research
project that has yielded groundbreaking results involving an unusual family
of crystalline minerals. Their findings could lay the groundwork for future
researchers seeking to develop a new generation of computer chips and other
information-storage devices that can hold vast amounts of data and be strongly
encrypted for security purposes.
Working with a team of researchers from various disciplines, Naresh S. Dalal
and Sir Harold W. "Harry" Kroto, both world-renowned chemists and
educators, took a close look at a family of crystals known as metal-organic
frameworks, or MOFs. Employing both laboratory experimentation and computational
analysis, they found that four such crystals possessed properties that rarely
coexist.
"We identified these four crystals as 'multiferroic,' meaning that they
are simultaneously ferromagnetic and ferroelectric in nature when cooled to
a specific temperature," said Dalal, Florida State's Dirac Professor of
Chemistry and Biochemistry. (Ferromagnetism means a material possesses magnetic
poles, while ferroelectricity refers to a material that possesses positive and
negative electrical charges that can be reversed when an external electrical
field is applied.)
"Normally, these two properties are mutually exclusive," Dalal said.
"Most materials are either ferromagnetic or ferroelectric based on the
number of electrons in the ion's outer electron shell. Therefore, finding four
multiferroic materials at one time is quite scientifically significant and opens
numerous doors in terms of potential applications."
Multiferroic materials have been a hot topic of research in recent years, with
researchers finding applications in the areas of hydrogen storage and the design
of advanced optical elements, among others. Kroto sees another potential use:
in the creation of high-powered computer memories and other data storage devices
that can hold far more information than is currently possible.
"Theoretically, it might be possible to design devices that are much
smaller and faster than the ones we use today to store and transmit data,"
said Kroto, a Francis Eppes Professor in Florida State's Department of Chemistry
and Biochemistry. "And with data split over two mediums, information could
be encrypted in a way that makes it far more secure than is currently possible.
This could have wide-ranging applications in areas as diverse as the aeronautics
industry, the military, the workplace and even the average consumer's home."
Dalal pointed to another possible benefit — high-tech devices that make
far less of an environmental impact.
"The four new multiferroic crystals that we have identified all substitute
other, less toxic metals for lead, which is a potent neurotoxin," he said.
"By reducing the amount of lead that enters landfills, we also reduce the
amount that enters our water supply — and our bodies."
Dalal, Kroto and their colleagues recently published a paper on their findings
in the peer-reviewed Journal of the American Chemical Society (JACS). Their
research was then summarized in a second article published in the prestigious
international science journal Nature — a powerful symbol of the significance
with which their findings have been greeted within the worldwide scientific
community.
"On the basis of the type of materials research I was keen to initiate
here at Florida State, it was natural to collaborate with Dr. Dalal due to his
deep understanding of the complexities of phase transitions," Kroto said.
"It is in particular the subtle aspects of phase behavior, well beyond
those traditional ones exhibited by normal gases, liquids and solids, that led
to this work being highlighted recently by Nature and Angewandte Chemie."
(The latter is a prominent, peer-reviewed scientific journal that reviews all
aspects of chemistry.)
In addition to Dalal and Kroto, other collaborators from Florida State were
Ronald J. Clark, an emeritus professor of chemistry and biochemistry who continues
to conduct research; Prashant Jain, a graduate research assistant; and Vasanth
Ramachandran, a graduate teaching assistant. Additional researchers were Haidong
Zhou, an assistant scholar/scientist at the National High Magnetic Field Laboratory
in Tallahassee; Anthony K. Cheetham, Professor of Materials Science and Metallurgy
at the University of Cambridge in England; and Brian H. Toby, a senior physicist
at Argonne National Laboratory in Illinois.
In the world of science, Dalal and Kroto are known as scientific heavy hitters,
each with decades of research experience and scores of professional accolades
to his credit. Kroto is perhaps best known as one of three recipients of the
1996 Nobel Prize for Chemistry and Biochemistry for his co-discovery of buckminsterfullerene,
a form of pure carbon better known as "buckyballs." He came to Florida
State in 2004 after 37 years at the University of Sussex in England. Dalal,
meanwhile, was recognized in 2007 as one of the top scientists in the southern
United States by the Memphis Section of the American Chemical Society, which
selected him to receive its Southern Chemist Award. That same year, he was named
the top chemist in Florida by the Florida Section of the American Chemical Society,
which bestowed upon him its annual Florida Award.