Pauling quickly demonstrated that he knew more about chemistry than many of his professors. While still an undergraduate he was asked to teach chemistry courses in the understaffed department, an experience that gave him self-confidence--he became a great lecturer--and access to current chemical journals. Teaching these courses also gave Pauling the opportunity to meet--and later marry--Ava Helen Miller, who was enrolled in his class as part of her home economics coursework.
By the time he graduated as a chemical engineer in he had set his sights on answering one of the most important questions of chemistry: how did atoms bond together to form molecules? In order to find out, he turned from chemical engineering to chemical theory. He enrolled in the first graduate program that offered adequate support, choosing a fledgling Pasadena research school, the California Institute of Technology, or Caltech.
Pauling became one of the first chemistry students in an outstanding doctoral program designed and overseen by the famed chemist Arthur Amos Noyes. Noyes pointed Pauling in the direction of a new experimental technique called x-ray crystallography, which enabled scientists to learn about the sizes and configurations of atoms within molecules and crystals. Pauling earned his Ph. His timing was propitious. A group of European physicists, including Niels Bohr, Werner Heisenberg, Wolfgang Pauli, Max Born, and Erwin Schroedinger--all of whom Pauling met--were creating new theories of atomic structure and behavior and fashioning a powerful advance in science called quantum mechanics.
Pauling learned the difficult theory, as well as the mathematics that underlay it, and was one of the first to bring this important advance back to the United States. Pauling returned to Caltech in as a faculty member, and began to apply quantum mechanics to problems of chemical structure and function. His work, The Nature of the Chemical Bond, encapsulated his ideas and quickly became a standard work in the field.
At the age of 38, Pauling was a full professor and head of the chemistry division at Caltech, the youngest member ever elected to membership in the National Academy of Sciences, and the father of four children three sons, Linus, Jr.
Pauling had started his structural studies by considering inorganic molecules, but during the s he shifted his structural studies to large biomolecules, especially proteins. His biomolecular research continued through World War II, during which Pauling--an avid anti-Nazi--also developed explosives and rocket propellants. During the s Linus Pauling was among the pioneers who used quantum mechanics to understand and describe chemical bonding - that is, the way atoms join together to form molecules.
Linus Pauling worked in a broad range of areas within chemistry. For example, he worked on the structures of biologically important chemical compounds. In he published the structure of the alpha helix, which is an important basic component of many proteins. Together with other scientists he spoke and wrote against the nuclear arms race, and he was a driving force in the Pugwash movement. It sought to reduce the role of nuclear arms in international politics and was awarded the Peace Prize in He was one of the prime movers who urged the nuclear powers the USA, the Soviet Union and Great Britain to conclude a nuclear test ban treaty, which entered into force on 10 October A multifaceted genius with a zest for communication, Linus Pauling for years was probably the most visible, vocal, and accessible American scientist.
A black beret worn over a shock of curly white hair became his trademark, along with a pair of lively blue eyes that conveyed his intense interest in challenging topics. He was a master at explaining difficult medical and scientific information in terms understandable to intelligent laypersons. He wrote numerous articles and books for the general public — on science, peace, and health. He was perennially sought as a speaker for conferences, political rallies, commencements, and media programs.
At the same time, Linus Pauling produced a multitude of scholarly scientific papers on an astounding variety of subjects in numerous research fields. Of the over 1, articles and books he published as sole or joint author, about two-thirds are on scientific subjects. His landmark book The Nature of the Chemical Bond is frequently cited as the most influential scientific book of the 20th century. Linus Pauling was never reluctant to inspire or enter into controversy by expressing unorthodox scientific ideas, taking a strong moral position, or rousing the public to some worthy cause.
He often provoked the scientific, medical, and political communities with his imaginative scientific hypotheses and strong social activism. He took professional and personal risks that most of his colleagues avoided. Steadfast and stubborn, yet rarely losing his cheerful equilibrium, he continued on his chosen and sometimes solitary path as a visionary of science and a prophet of humanity.
To give one example of his committed yet free-spirited nature: In , during the Kennedy administration, the Paulings were invited to a special party at the White House honoring Nobel laureates.
Pauling spent the day outside the gates carrying a placard that protested atmospheric nuclear testing. Then that evening, he and his wife sat down to an elegant dinner with the Kennedys. And, when energetic music was played, the couple felt inspired to get up and dance — to the delight of onlookers.
Over the seven decades of his scientific career, Pauling's research interests were amazingly wide-ranging and eclectic. He made important discoveries in many different fields of chemistry — physical, structural, analytical, inorganic, and organic chemistry, as well as biochemistry. He used theoretical physics, notably quantum theory and quantum mechanics, in his investigations of atomic and molecular structure and chemical bonding.
He ventured into metallurgy and mineralogy through the study of atomic structures and bonding of metals and minerals and, with his colleagues, published the structures of hundreds of inorganic substances, including topaz and mica.
In both theoretical and applied medicine, he made important discoveries in genetic diseases, hematology, immunology, brain function and psychiatry, molecular evolution, nutritional therapy, diagnostic technology, statistical epidemiology, and biomedicine.
Much of Pauling's lifework combined the dedication and knowledge of the scientist with a deep commitment to humanitarianism that espoused his own operating ethical principle of the "minimization of suffering.
He received his early education in Oregon, finishing in with a bachelor's degree in chemical engineering from Oregon Agricultural College in Corvallis — now Oregon State University. Already he was drawn to the challenge of how and why particular atoms form bonds with each other to create molecules with unique structures.
For postgraduate study, Pauling went to the California Institute of Technology Caltech , which provided a stipend for research and teaching. In he received a Ph.
Awarded a Guggenheim Fellowship, in he studied in Europe with physicists who were exploring the implications of quantum mechanics for atomic structure.
In this revolutionary new field, Pauling found a physical and mathematical framework for his own future theories regarding molecular structure and its correlation with chemical properties and function. After Linus Pauling joined the Caltech faculty in the autumn of , he continued his intensive research on the formation of chemical bonds between atoms in molecules and crystals.
To chart bond angles and distances characteristic of particular atoms in relation to other atoms, he used x-ray diffraction learned earlier as a graduate student — supplemented after by electron diffraction, an even newer technique that he brought to the U. Quantum mechanics enabled Pauling to explain the bonding phenomenon theoretically in a far more satisfactory way than before.
He began to formulate generalizations regarding the atomic arrangements in crystals with ionic bonding, in which negatively charged electrons, orbiting around the positively charged nucleus, are transferred from one atom to another.
Pauling discovered that in many cases the type of bonding — whether ionic or covalent formed by a sharing of electrons between bonded atoms — could be determined from a substance's magnetic properties. He also established an electronegativity scale of the elements for use in bonds of an intermediate character having both ionic and covalent bonding ; the smaller the difference in electronegativity between two atoms, the more the bond between them approaches a purely covalent bond.
To explain covalent bonding, Pauling introduced two major new concepts, based on quantum mechanics: bond-orbital hybridization and bond resonance. Hybridization reorganizes an atom's electron cloud so that some electrons assume positions favorable for bonding. Since the carbon atom can form four bonds, tetrahedrally arranged — a central structural feature of organic chemistry — Pauling's explanation of it and of many related features of covalent bonding attracted attention from chemists around the world.
Resonance is a rapid jumping of electrons back and forth between two or more possible positions in a bond network. Resonance makes a major contribution to the structural geometry and stability of many substances, such as benzene or graphite, for which a static, non-resonating bond system would be inadequate. Pauling later extended his bond resonance concept to a theory of bonding in metals and intermetallic compounds. Pauling's innovative concepts, published beginning in the late s, together with numerous examples of their application to particular chemical compounds or compound groups gave chemists fundamental principles to apply to the growing body of chemical knowledge.
They could also accurately predict new compounds and chemical reactions on a theoretical basis that was far more satisfactory than the straight empiricism of pre-Pauling chemistry. In Pauling brought together his work on these subjects in his definitive book The Nature of the Chemical Bond and the Structure of Molecules and Crystals, which became a classic and was translated into many languages. Its third edition appeared in and has remained in print to this day. Pauling's interest in molecular structure continued throughout his long career, and the theoretical calculations involved meant utter happiness to him.
He used what he called the "stochastic method," which drew upon his own encyclopedic knowledge and formidable memory and allowed him to postulate a likely molecular structure, based on reasoning and theoretical calculation. Detailed laboratory verifications would often be carried out by associates — as with most of his research projects.
Many of his discoveries and inventions were then expanded upon and utilized profitably in the industry by others. And though in later years he was primarily involved in biomedical research, his curiosity often impelled him to identify the intricate structures of many clay minerals, transition metals, intermetallic compounds, and other substances.
In he was awarded one of his last patents for a novel technique of fabricating superconductive materials. In the early s, Pauling took over the teaching of freshman chemistry at Caltech.
His modern theoretical approach to chemistry, charismatic lecturing style, and energetic showmanship the laboratory demonstrations occasionally become pyrotechnical displays made him a very popular professor. He also told students about his current research, giving them insight into the professional chemist's work. In he put his new approach to chemical education into General Chemistry, a textbook that greatly influenced the teaching of chemistry worldwide by redirecting it from its traditional, purely empirical basis into the new "chemical bond approach.
Pauling's involvement with human physiology and health, which dominated the last three decades of his research career, had long precedents. During the mids a significant part of his research, generously funded by the Rockefeller Foundation, moved into biochemistry — a field he had previously avoided — as he became increasingly interested in the highly complex molecules within living organisms. Applying techniques used in earlier diffraction studies to biological compounds, he now sought to understand the structure of proteins.
In he investigated the magnetic properties of hemoglobin, the oxygen-carrying molecule in red blood cells. He then studied the roles of antigens and antibodies in the immune response, one aspect of the important phenomenon of specificity in biochemical interactions.
In he made the novel proposal that this specificity is achieved through molecular complementariness, which he regarded as the secret of life. The concept — involving a "hand-in-glove" fit of one molecule against or into another molecule that has a shape complementary to the first — was tested in his laboratory over the next 10 years by means of numerous serological experiments, yielding results published in no less than 34 scientific papers.
In Pauling postulated that the gene might consist of two mutually complementary strands — a concept anticipating Watson and Crick's discovery of DNA structure seven years later.
Pauling originated the concept of molecular disease. In , while hearing a physician describe sickle cell anemia, he instantly surmised that it might be caused by a defect in the red blood cell's hemoglobin. After three years of painstaking research, he and his associate Dr. Harvey Itano identified this prevalent disease as molecular in origin — caused by a genetically transmitted abnormality in the hemoglobin molecule.
In susceptible patients, hemoglobin molecules in venous blood, lacking oxygen, become self-complementary; distorted, they stick together and form long rods that interfere with blood circulation. Pauling's description of this first molecular disease as he called it initiated a search for many more such disorders. The new idea quickly became immensely important in medicine and is now the main focus of human genome research. Thus the medical specialties of hematology, serology, immunology, applied genetics, and pathology owe much to Pauling's contributions, which were made long before his intense interest in the promise of nutritional therapy became widely known.
Pauling offered the U. He devised some impressive explosives one called "Linusite"! He invented a meter that monitored oxygen levels in submarines and airplanes; the device later provided invaluable in ensuring safe levels of that life-sustaining gas for premature infants in incubators and for surgery patients under anesthesia.
With an associate, Dr. Pauling originated a synthetic form of blood plasma for use in emergency transfusions in battlefield clinics.
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