Vigyan Prasar Science Portal
For anything and everything on science from India
Home
Linus Carl Pauling
The Greatest Architect of Modern Chemistry
 
 
 
Dr Subodh Mahanti

 


It is when we take some interest in the great discoverers and their lives that science becomes endurable and only when we begin to trace the developments of ideas that it becomes fascinating.

James Clerk Maxwell

The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.

William Lawrence Bragg in Beyond Reductionism (1968)

The personal lives of geniuses are as complex as those of ordinary mortals. Intellectual brilliance, after all, does not necessarily guarantee moral integrity, personal charm, political rectitude, or any other desirable character trait. So one should hardly be surprised that Linus Pauling's life and personality have been assessed in a myriad of ways by his contemporaries.

The one point on which no one disagrees is his brilliance as a scientist. Probably the most prolific and one of the best-known science writers of all time, Isaac Asimov, has called him "a first-class genius, "the greatest chemist of the 20th century". Pauling's numerous honorary degrees and awards confirm this judgment. His colleagues have honoured him at one time or another with every high honour in chemistry.


David E. Newton in his Linus Pauling: Scientist and Advocate, Universities Press (India) Ltd. 1999.

 


[The idea of writing on Pauling cropped up after writing on G.N. Ramachandran (Dream-2047, September 2001 Issue), who was greatly influenced by Pauling. We had reproduced the poem written by Ramachandran on Pauling. Moreover the year 2001 also happens to be the birth centenary of Pauling].

Linus Carl Pauling is the only person to have received two unshared Nobel Prizes - first in 1954 in chemistry for his 'research into the nature of the chemical bond and its application to the elucidation of the structure of complex substances', and the second one in 1962 in Peace for his ardent pacifist campaign against nuclear warfare. Pauling is widely regarded as one of the greatest scientists ever. Besides being the greatest architect of chemistry, Pauling was a founder of molecular biology and a pioneer in quantum mechanics. Pauling combined chemistry and physics to solve various puzzles related to the nature of chemical bond. As one of his biographers has written Pauling's understanding of the chemical bond and molecular architecture is probably unsurpassed in the history of chemistry. His ideas on chemical bonding are fundamental to modern theories of molecular structure. Pauling determined crystal structure by X-ray crystallography and the structure of gas molecules by electron diffraction. He ascertained the molecular cause of sickle-cell anaemia and his observation that a molecular disorder can explain the symptoms of an illness founded the discipline, molecular medicine. He developed an electronegativity scale to assigning electronegativities to atoms involved in covalent bonding. He extended the theory of covalent bonds to include metal and intermetallic compounds. It was Pauling who formulated the concept of resonance, a very important concept in structural chemistry. It refers to a state where none of the classical formulae of a chemical system is entirely consistent with observed properties. Pauling developed unique model building techniques that he put to use in his studies of proteins and nucleic acids. He proposed helical structures for proteins based on polarity of the atoms in the peptide bond. His monumental text book, The Nature of the Chemical Bond and the Structure of Molecules and Crystals, first published in 1939, is even today a classic in its field. The book is one of the most important books in the history of chemistry. It has been translated in many languages.

Pauling is much known for his controversial thesis proposing that high doses of vitamin-C would help not only in the prevention of common cold but also in the prevention of cancer. In 1973, he founded the Linus Pauling Institute of Science and Medicine in Palo Alto, California. Outside his scientific works, Pauling took a vital interest in public affairs, especially in the movement for world disarmament. His book No More War (1958) was a plea for international peace. It was an instant best-seller. He strongly opposed nuclear testing. He could gather signature and support of 11,000 scientists for his petition against nuclear testing in front of the United Nations. Pauling was well-known for his independence, courage, fighting qualities, brilliant wit and vigorous enthusiasm for his work. Isaac Asimov called him 'a gentleman in highest sense of the word." Pauling was a very controversial and outspoken person. His uncompromising nature was reflected even in his school days.

Pauling was born in Portland, Oregon, USA on 28th February 1901. His parents were Herman Henry William Pauling, a pharmacist and Lucy Isabelle Pauling usually called Belle. His father died when Pauling was 9 years old, forcing him to take up odd jobs to support his mother and sisters as well as pay for his education.

We are told that by the age of nine Pauling had read all the books available in his house. Pauling's father Herman Pauling, in his attempt to collect proper reading material for young Pauling, wrote to a local newspaper, the Oregonian : "I am a father and have an only son who is aged 9 years, in the fifth grade, a great reader and is deeply interested in ancient history….. In my desire to encourage and assist him in his prematurely developed inclinations I ask some of the Oregonian's interested readers to advise me regarding the proper or atleast the most comprehensive works to procure for him." we are told that Herman Pauling did not receive any response.

Pauling's interest in science developed at the very early age of 11. Pauling started collecting first insects and then minerals. It is said that he did not stop at collecting the objects but he proceeded to classify and catalogue them. However, in his own words Pauling was not successful as a collector. To quote Pauling: "I was not successful as a collector, but I got a book from the library on mineralogy and I copied out tables of properties, hardness and various properties, on to sheets of papers and glued the papers to the wall in my work room."

In 1914 Pauling graduated from the Sunnyside Grammar School and entered Portland's Washington High School. It is here that Pauling became interested in studying chemistry. He was influenced by one of his friends named Lloyd Jeffress, who had set up a small laboratory in the corner of his bedroom. Pauling became fascinated with chemistry after watching Jeffress conduct some simple experiments. To quote Pauling : "I decided then to be a chemist and to study chemical engineering, which was, I thought, the profession that chemists followed:" Following his friend Jeffress, Pauling also built a small laboratory in the basement of his house. He carried out a lot of experiments on his own. He borrowed the chemicals needed for his experiments from a small chemical laboratory at the abandoned Oregon Iron and Steel Company in Oswego. This was possible because Pauling's grandfather was a night watchman at a nearby plant. Later recalling his early interest in chemistry Pauling would write: "I was simply entranced by chemical phenomena, by the reaction in which substances disappear and other substances, often with strikingly different properties, appear."

Sickle-cell Anaemia: A Molecular Disease

Sickel-cell anaemia is a hereditary chronic blood disorder in which a person’s blood cells contain an abnormal form of haemoglobin, the protein that transports oxygen and which become incapable of carrying oxygen efficiently. This often results in anaemia. When the blood is deprived of oxygen the abnormal haemoglobin crystalises and distorts the red blood cells into a sickle shaped. The presence of sickle cells in the blood with or without accompanying anaemia, is called sicklemia. The disease principally affects the black population of Central Africa. Three different types of individuals occur in such populations – those who have two genes for normal haemoglobin and therefore do not suffer from the disease; those with one abnormal gene and one normal gene and are likely to suffer from anaemia and those with two abnormal genes who suffer a chronic and eventually fatal form of anaemia.

Pauling thought that it was an abnormality in oxygen-carrying haemoglobin molecule found in red blood cells and not the abnormality of the red blood cells themselves that caused the sickle cell anaemia. Before turning to sickle cell anaemia Pauling was working in haemoglobin. Pauling and his student Dr. Harvey Itano demonstrated that haemoglobin found in people having sickle cell anaemia actually differ from normal haemoglobin molecule. Though the difference was very modest. Only one of a total of 146 amino acids in such haemoglobin molecule is incorrect. But such a single error was enough to alter haemoglobin and reduce its ability to transport oxygen.

Here we will discuss in little detail how Pauling worked hard for continuing his education, with a view that it may act as a source of inspiration to younger people. Unlike many fortunate children, Pauling had to arrange money himself for his studies. Before joining Oregon Agricultural College at Corvallis, Pauling was working at a machine shop, where he was earning $100 a month and his employer had promised to increase his salary to $250 a month provided he decided to stay there. Pauling's mother was not in favour of his joining the college. As stated earlier Pauling's father died when he was nine years old. So his mother wanted Pauling to stay at home and help her financially as she still had two young children to raise. However, Pauling decided to join the college. Since his mother had no means to help him, Pauling had to earn enough to meet all his college expenses. The expenses were not very high. The college did not charge any tuition fees and the books were inexpensive. He lived in a cheap boarding house, where he shared a room with a fellow student. But still he had to work hard. Describing a job of delivering milk undertaken by him at the age of 18 he wrote: " a very hard job, working eight hours every night from about eight o'clock to about four o'clock with a horse pulling the milk wagon and delivering milk to about 500 customers."

Inspite of the hard work that he had to undertake to meet his college expenses, Pauling was able to impress his teachers and colleagues by his studies. He had very little social life. As his financial problem continued Pauling took up a job of paving-plant inspector of the State of Oregon during the summer of 1919. His job was to inspect new pavement and take samples back to the state laboratory for analysis. His salary for the job was $125 per month. He lived in a tent with the workmen and ate with them. He sent almost his entire salary to his mother, expecting that his mother would be able to help him to return to Oregon Agricultural College for his junior year. However, the financial crisis grew worse. His mother was suffering from pernicious anaemia. So he was compelled to decide to continue to work as leaving-plant inspector. But then he got an offer from Oregon Agricultural College to teach quantitative analysis in chemistry. The offer was really extraordinary considering the fact that Pauling was a student, who completed the course himself six months earlier. The salary for his new assignment was $100-a-month. His duties were to supervise laboratories and give lectures. He had to spend 40 hours a week with students. Besides his teaching assignment Pauling studied the works of two eminent chemists Gilbert Newton Lewis (1875-1946) and Irving Langmuir (1881-1957). Their works had a profound effect on Pauling. This had largely determined the course of his work for fifty years. As