Alan MacDiarmid

Alan MacDiarmid
Born	Alan Graham MacDiarmid 14 April 1927
Birthplace	Masterton, New Zealand
Died	7 February 2007 (aged 79) Drexel Hill, Pennsylvania, United States
Nationality	New Zealand, American
Occupation	Chemist
Known for	Discovery and development of conducting polymers
Education	Ph.D., University of Cambridge (1955)
Awards	Nobel Prize in Chemistry (2000), Order of New Zealand
Website	[http://www.sas.upenn.edu/~macdiarm/ Official site]

Alan Graham MacDiarmid, ONZ FRS (14 April 1927 – 7 February 2007), was a New Zealand-born American chemist whose groundbreaking work on electrically conducting polymers transformed the understanding of plastics and opened new frontiers in materials science. Born into modest circumstances in the small town of Masterton, New Zealand, MacDiarmid rose through academic scholarship and relentless curiosity to become one of the most distinguished chemists of the twentieth century. In 2000, he shared the Nobel Prize in Chemistry with Alan J. Heeger and Hideki Shirakawa for "the discovery and development of conducting polymers." MacDiarmid spent the majority of his career at the University of Pennsylvania, where he was Blanchard Professor of Chemistry. His research demonstrated that certain organic polymers—materials traditionally considered insulators—could be chemically modified to conduct electricity, a discovery with profound implications for electronics, energy storage, and sensor technologies. MacDiarmid maintained strong ties to New Zealand throughout his life, and at the time of his death in February 2007, he was preparing to travel to his homeland.

Early Life

Alan Graham MacDiarmid was born on 14 April 1927 in Masterton, a town in the Wairarapa region of New Zealand's North Island. He was one of five children in a family of modest means. His father worked as an engineer, and the family experienced financial hardship, particularly during the Great Depression years of the 1930s.

The MacDiarmid family later relocated to Lower Hutt, near Wellington, in search of better economic prospects. Growing up during a period of economic hardship, young Alan developed resourcefulness and a deep intellectual curiosity at an early age. His interest in chemistry was sparked around the age of ten when he found one of his father's old textbooks on the subject. He later recalled being captivated by the book and reading it cover to cover, despite not understanding much of its contents at first. This early encounter with chemistry set the trajectory for his life's work.

MacDiarmid attended Hutt Valley High School in Lower Hutt, where he continued to develop his interest in the sciences. Despite the family's limited financial resources, education was valued in the MacDiarmid household, and Alan excelled academically. He took part-time jobs to help support himself and contribute to the family while pursuing his studies. One such job involved working as a janitor and laboratory assistant at Victoria University College (now Victoria University of Wellington), where he was simultaneously enrolled as a student—an arrangement that allowed him to fund his own education while gaining hands-on experience in a laboratory setting.

This early exposure to laboratory work, combined with his natural aptitude for chemistry, reinforced MacDiarmid's determination to pursue a career in scientific research. His upbringing in New Zealand, marked by both hardship and intellectual aspiration, shaped his character and his lifelong commitment to making science accessible to young people from all backgrounds.

Education

MacDiarmid began his tertiary education at Victoria University College in Wellington, New Zealand, where he worked part-time to support his studies. He earned both a Bachelor of Science and a Master of Science degree from Victoria University College, with his master's research focusing on aspects of chemistry that would foreshadow his later interests in inorganic and materials chemistry.

After completing his studies in New Zealand, MacDiarmid was awarded a Fulbright Fellowship, which enabled him to pursue further graduate studies at the University of Wisconsin–Madison in the United States. He earned a Master of Science degree from Wisconsin.

MacDiarmid subsequently received a Shell Graduate Scholarship to undertake doctoral research at the University of Cambridge in England. At Cambridge, he completed his Ph.D. in 1955, with a thesis entitled "The chemistry of some new derivatives of the silyl radical." This doctoral work, carried out under the supervision of H.J. Emeléus, focused on silicon chemistry and established MacDiarmid's expertise in inorganic synthesis—skills that would prove essential in his later, Nobel Prize-winning research on conducting polymers.

Following his doctoral studies at Cambridge, MacDiarmid also spent time at the University of St Andrews in Scotland before returning to the United States to begin his academic career.

Career

Early Academic Career at the University of Pennsylvania

In 1955, MacDiarmid joined the faculty of the University of Pennsylvania in Philadelphia as a member of the Department of Chemistry. He would remain affiliated with Penn for over five decades, eventually rising to the position of Blanchard Professor of Chemistry, one of the most prestigious chairs in the department.

During the early years of his career at Penn, MacDiarmid's research focused primarily on silicon chemistry and inorganic compounds, building on the foundations laid during his doctoral work at Cambridge. He developed expertise in the synthesis and characterization of novel inorganic materials, including work on sulfur nitride polymers. It was this work on sulfur nitride—a polymeric inorganic material with metallic properties—that would eventually lead MacDiarmid toward the research for which he became most famous.

MacDiarmid's research group at Penn became known for its collaborative and international character. Over the decades, he mentored numerous graduate students and postdoctoral researchers from around the world, many of whom went on to distinguished careers in chemistry and materials science.

Discovery of Conducting Polymers

The research that would ultimately earn MacDiarmid the Nobel Prize began in the mid-1970s, arising from a serendipitous encounter and a series of cross-disciplinary collaborations. The story of conducting polymers is one of the most celebrated examples of how chance and curiosity can converge to produce transformative scientific breakthroughs.

In 1975, MacDiarmid was visiting Tokyo Institute of Technology in Japan, where he encountered Hideki Shirakawa, a Japanese chemist who had been working on polyacetylene—a polymer of acetylene. Shirakawa had accidentally produced a silvery film of polyacetylene that was visually striking due to its metallic sheen. This accidental synthesis had occurred when a student in Shirakawa's laboratory used a much higher concentration of catalyst than intended, producing the film form of polyacetylene rather than the usual powder.

MacDiarmid, whose experience with sulfur nitride polymers made him immediately alert to the potential significance of a polymer with metallic appearance, invited Shirakawa to visit his laboratory at the University of Pennsylvania. There, in collaboration with physicist Alan J. Heeger, who was also at Penn, the three scientists undertook experiments to modify the electrical properties of polyacetylene.

In 1977, MacDiarmid, Heeger, and Shirakawa made their landmark discovery: by exposing polyacetylene films to iodine vapor—a process known as "doping," borrowed from semiconductor terminology—they could increase the polymer's electrical conductivity by a factor of more than ten million. The doped polyacetylene achieved conductivity levels approaching those of metals—a result that challenged the long-held assumption that organic polymers (plastics) were inherently electrical insulators.

This discovery was revolutionary for several reasons. First, it demonstrated that the boundary between conductors and insulators was not as rigid as previously believed. Second, it introduced the concept that the electronic properties of organic materials could be precisely tuned through chemical modification. Third, it opened an entirely new field of research—sometimes termed "synthetic metals" or "organic electronics"—with far-reaching practical implications.

The Royal Swedish Academy of Sciences, in awarding the 2000 Nobel Prize in Chemistry to the three researchers, cited "the discovery and development of conducting polymers" as the basis for the award. The Academy noted that the discovery had given rise to a new field of research at the intersection of chemistry and physics, with applications ranging from light-emitting diodes and solar cells to anti-static coatings and electromagnetic shielding.

Polyaniline and Later Research

Following the initial polyacetylene work, MacDiarmid continued to make significant contributions to the field of conducting polymers. He became particularly known for his extensive research on polyaniline, another conducting polymer that offered several practical advantages over polyacetylene, including greater environmental stability and easier processability.

Polyaniline, derived from the monomer aniline, had been known since the nineteenth century as an organic dye (aniline black), but MacDiarmid and his collaborators demonstrated that it could be rendered electrically conductive through acid-base chemistry—a simpler and more controllable process than the halogen doping used with polyacetylene. MacDiarmid's work on polyaniline contributed to making conducting polymers more practical for real-world applications, as polyaniline could be processed from solution, was more stable in air, and could be produced at lower cost than many other conducting polymers.

MacDiarmid's research group published extensively on the synthesis, characterization, and applications of polyaniline and related materials throughout the 1980s and 1990s. His work helped establish the fundamental understanding of how chemical structure, doping level, and processing conditions influence the electronic and optical properties of conducting polymers.

International Collaborations and Outreach

Throughout his career, MacDiarmid was committed to fostering international scientific collaboration. His initial partnership with Shirakawa in Japan exemplified this approach, and he maintained active research collaborations with scientists in numerous countries, including New Zealand, China, Brazil, and South Korea.

MacDiarmid held visiting professorships and honorary positions at several institutions outside the United States. He was particularly active in promoting scientific research and education in the Asia-Pacific region. He visited China on multiple occasions and was involved in efforts to strengthen scientific ties between the United States and China.

MacDiarmid also maintained a strong connection to his native New Zealand throughout his career. He returned frequently to lecture and collaborate with New Zealand scientists, and he was a strong advocate for increased government investment in scientific research in New Zealand. He was involved with the MacDiarmid Institute for Advanced Materials and Nanotechnology, a New Zealand Centre of Research Excellence established at Victoria University of Wellington and named in his honor.

His commitment to education extended to mentoring young scientists. MacDiarmid frequently spoke about the importance of curiosity-driven research and the value of making science accessible to people from all socioeconomic backgrounds, drawing on his own experience of growing up in financial hardship in New Zealand.

Applications of Conducting Polymers

The field that MacDiarmid helped create expanded rapidly in the decades following the initial 1977 discovery. Conducting polymers found applications in a wide range of technologies. Organic light-emitting diodes (OLEDs), used in display screens for smartphones, televisions, and other devices, rely on the principles of electrically active organic materials that MacDiarmid and his collaborators helped establish. Other applications include organic solar cells, electrochromic windows, anti-corrosion coatings, chemical and biological sensors, rechargeable batteries, and supercapacitors.

The 2000 Nobel Prize press release noted that the practical applications of conducting polymers were already becoming apparent, with anti-static coatings, "smart windows" that could change their opacity in response to an electrical signal, and prototype electronic devices based on organic semiconductors all in development or commercialization.

Personal Life

MacDiarmid married his first wife, Marian Mathieu, with whom he had several children. After her death, he married Gayl Gentile. He became a United States citizen while maintaining his deep attachment to New Zealand.

MacDiarmid was known among colleagues and students for his warmth, generosity, and enthusiasm for science. Despite his international stature and Nobel laureate status, he remained accessible and approachable, often engaging with students and young researchers with genuine interest and encouragement.

MacDiarmid frequently spoke about his New Zealand roots and the formative influence of growing up during a time of economic hardship. He credited his early experiences—including his part-time work as a janitor at Victoria University College—with instilling in him a strong work ethic and an appreciation for the opportunities that education could provide.

Alan MacDiarmid died on 7 February 2007 at his home in Drexel Hill, Pennsylvania, a suburb of Philadelphia. He was 79 years old. According to reports, his death followed a fall at his home; he had been preparing to depart for a visit to New Zealand at the time. His colleague Alan Heeger wrote that MacDiarmid's "health had been failing over the last years," but that he had remained intellectually active and engaged with science until the end of his life.

Recognition

MacDiarmid received numerous awards and honors over the course of his career, culminating in the 2000 Nobel Prize in Chemistry.

The Nobel Prize in Chemistry was awarded jointly to MacDiarmid, Alan J. Heeger, and Hideki Shirakawa by the Royal Swedish Academy of Sciences in October 2000 "for the discovery and development of conducting polymers." At the Nobel ceremonies in Stockholm in December 2000, all three laureates delivered lectures and participated in public events. In a joint interview, the three scientists discussed the collaborative nature of their discovery and the serendipitous circumstances that brought them together. In his banquet speech, Heeger acknowledged the shared nature of the prize and the central role that MacDiarmid and Shirakawa played in the discovery.

MacDiarmid was appointed to the Order of New Zealand (ONZ), the highest honor in the New Zealand honors system, limited to no more than twenty living members at any time. This appointment recognized his contributions to science and his role as a distinguished New Zealander on the world stage.

He was elected a Fellow of the Royal Society (FRS), one of the most prestigious distinctions in international science. He also received the American Chemical Society Award in the Chemistry of Materials, among other honors from professional scientific organizations.

MacDiarmid received honorary degrees from several universities worldwide. The University of Pennsylvania celebrated his Nobel Prize with considerable institutional pride, holding events and publishing features highlighting his decades-long association with the university.

Legacy

Alan MacDiarmid's contributions to chemistry and materials science have had lasting effects on both fundamental research and technological development. The field of conducting polymers that he helped create has grown into a major area of scientific inquiry, encompassing thousands of researchers worldwide and generating a vast body of published literature.

The practical applications of conducting polymers have continued to expand since MacDiarmid's death. Organic electronics—including OLEDs, organic photovoltaics, and flexible electronic devices—represent a multibillion-dollar industry that traces its scientific origins to the work of MacDiarmid, Heeger, and Shirakawa in the late 1970s. The fundamental insight that organic materials could be made to conduct electricity has influenced research in fields as diverse as bioelectronics, energy harvesting, and environmental sensing.

In New Zealand, MacDiarmid's legacy is preserved through the MacDiarmid Institute for Advanced Materials and Nanotechnology, a national Centre of Research Excellence headquartered at Victoria University of Wellington. The Institute supports research in advanced materials science and nanotechnology, and its establishment reflects MacDiarmid's commitment to fostering scientific research and education in his home country.

The University of Pennsylvania has honored MacDiarmid's memory through various commemorations and through the continued activity of the research programs he helped build. His former colleagues have noted that his mentorship of students and junior scientists was among his most important contributions, as the researchers he trained have gone on to lead laboratories and research programs around the world.

MacDiarmid's life story—from a childhood of economic hardship in small-town New Zealand to the Nobel Prize podium in Stockholm—has been cited as an example of the transformative power of education and scientific curiosity. His career demonstrated that major scientific discoveries can emerge from unexpected collaborations and serendipitous encounters, and that researchers from any background can make contributions of the highest order to human knowledge.

A biographical memoir published by the National Academy of Sciences provides a detailed account of MacDiarmid's scientific contributions and personal history, ensuring that a comprehensive record of his life and work is preserved for future generations of scientists.