Haber, Fritz

Haber, Fritz

(b. Breslau, Germany [now Wroclaw, Poland], 9 December 1868; d. Basel, Switzerland, 29 January 1934)

chemistry.

Haber’s mother died when he was born. His father, who sold pigments and dyestuffs, was one of Gerrmany’s largest importers of natural indigo. Haber’s early schooling was at the Volksschule and the St. Elisabeth Gymnasium. He attended the universities of Berlin and Heidelberg and the Charlottenburg Technische Hochschule; the latter school awarded him the Ph. D. in 1891. After little more than a year of employment at three different factories, Haber entered the Eidgenössische Technische Hochschule at Zurich, Switzerland, as a postdoctoral student in chemical technology and studied principally with Georg Lunge. Six months spent in his father’s business proved to be unsatisfactory, and he became an assistant to Ludwig Knorr at the University of Jena and then to Hans Bunte at the Karlsruhe Technische Hochschule. He received Privatdozent status at the Baden school following publication of his first book, Experimentelle Untersuchungen über Zertsetzgung and Verbrennung von Kohlenwasserstoffen (“Experimental Studies on the Decomposition and Combustion of Hydrocarbons” [Munich, 1896]).

This record of his research exemplifies the work for which Haber became famous: theoretical studies, done with insight and thoroughness, in areas of growing practical importance. The thermal decomposition of hydrocarbons had been investigated extensively by Marcelin Berthelot twenty-five years earlier; Haber criticized Berthelot’s conclusions as arbitrary. He found the carbon-to-carbon linkage in hydrocarbons to have a greater thermal stability than the carbon-to-hydrogen linkage in aromatic compounds; the reverse was true for aliphatic compounds. This rule has been shown to be subject to exceptions.

In 1901 Haber married Dr. Clara Immerwahr, also a chemist. A son, Hermann, was born in June 1902. During the autumn of 1917, two and one-half years after the death of his first wife, he married Charlotta Nathan. Two children, Eva and Ludwig, were born; the marriage ended in divorce in 1927.

After being named Privatdozent, Haber turned to problems of physical chemistry, although he had no formal education in this area. He had the help of his colleague Hans Luggin, a pupil of Svante Arrhenius, but Haber considered himself self-taught in the field. He first investigated the electrochemical reduction of nitrobenzene and showed the importance of electrode potential. He studied the nature and rate of the electrode process for the quinine-quinol system and, interested in the nature and rate of the electrode process, did not emphasize the application to the measurement of hydrogen ion concentration. Later he devised a glass electrode to measure hydrogen ion concentration through the electric potential across a piece of thin glass. Other electrochemical subjects investigated by Haber include fuel cells; measurement of the free energy of oxidation of hydrogen, carbon monoxide, and carbon; and the electrolysis of crystalline salts. At the end of his career he had an active interest in electrochemistry, studying autoxidation; application of Planck’s quantum theory to chemistry was the basis of most of his later work. In 1898 he published his Grundriss der technischen Elektrochemie auf theoretischer Grundlage at Munich and was promoted to associate professor. As an indication of his growing reputation, in 1902 the Deutsche Bunsen-Gesellschaft sent him on a sixteen-week study tour of the United States. His report on chemical education and electrochemical industry in the country was acclaimed in Europe and America.

In 1905 Haber’s Thermodynamck technischer Gasreaktionen Vorlesungen was published at Munich, and in 1906 he was given a full professorship. Gilbert Lewis and M. Randall’s classic text, Thermodynamics and the Free Energy of Chemical Substances, published in 1923, described Haber’s book as “a model of accuracy and critical insight.”

Haber’s outstanding accomplishment in chemistry, during the first decade of the twentieth century, involved a gas reaction. He was one of many scientists interested in nitrogen fixation. As in virtually all his work, the problem had both theoretical and practical significance, and he looked into several possible solutions. Walther Nernst, a leader in physical chemistry, obtained data at variance with Haber’s for the combination of nitrogen and hydrogen to form ammonia. Nernst presented measurements from experiments done at high pressure and can be considered the first to accomplish the synthesis under these conditions. (Henry Le Chatelier had been the first to try the high-pressure synthesis, but an explosion induced him to forsake the venture.) Haber considered the difference in values a personal challenge. Working with Robert Le Rossignol, a student from the Isle of Jersey, and assisted by the mechanic Kirchenbauer, he performed high-pressure experiments and confirmed his earlier results, done at atmospheric pressure, which Nernst had questioned. A constant used by Nernst in his calculations—not his heat theorem—was later shown to be the cause of the erroneous values.

Haber went on to commercial exploitation of the synthesis of ammonia. His calculations showed that about 8 percent ammonia was available at pressures of 200 atmospheres and temperatures of 600°C. However, it was through the work of others that the process came to be the first successful high-pressure industrial chemical reaction. Such practical problems as a satisfactory, long-lasting container for the operation were solved under the direction of Carl Bosch and his associates at the Badische Anilin- and Sodafabrik. Nonetheless, users and students of highpressure techniques came to Haber’s laboratory for instruction.

In 1912 Haber became director of the Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry at Dahlem, on the outskirts of Berlin. His friend Richard Willstätter was codirector, with Ernst Beckmann, of the first of these Kaiser Wilhelm research institutes, for chemistry.

At the start of World War I, Haber placed himself and his laboratory at the service of his country. Assigned problems involving the supply of war materials, he showed xylene and solvent naphtha to be good substitutes for toluene as an antifreeze in benzene motor fuel. The War Ministry consulted Walther Nernst about using irritants to drive the Allies out of their trenches so’ that open warfare might be resumed; Haber was given a share in solving this problem. Dianisidine chlorosulfonate, an irritant powder suggested by Nernst, and the lacrimator xylyl bromide proved to be ineffective. Haber’s laboratory studied other irritants and the investigation came to a close in December 1914 with an explosion when a few drops of dichloromethylamine were added to a few cubic centimeters of impure cacodyl chloride. Otto Sackur, an outstanding physical chemist, was killed.

Haber developed the use of chlorine gas as a war weapon; by the end of January 1915 the preliminary laboratory research was completed. On 11 April 1915 about 5,000 cylinders of the gas were distributed, and the chemical was released over a 3.5-mile front near Ypres, Belgium. German military leaders later admitted that had massive attacks rather than the small test been done, German victory would have been assured. Instead, the Allies soon developed gases and the weapon on both sides was no longer intended to move men but to kill them.

In 1916 Haber became chief of the Chemical Warfare Service; and although he was only a captain, every detail of chemical offense, defense, supply, and research came under his supervision. By that time his process of nitrogen fixation was used in supplying Germany with nitrogen compounds, needed for fertilizers and for the explosives that provided staying power after the United States’s entry into the war.

In November 1919 Haber was awarded the Nobel Prize in chemistry. The honor was denounced by some French, British, and American scientists, which dealt another blow to his spiritual and physical condition. Having put all his energies into the war, he was obliged to share personally in Germany’s defeat. To be condemned as inhuman by fellow scientists also involved in war work deeply troubled him.

During the early postwar years Haber continued his patriotic efforts. He was the leading figure in appeals for the Notgemeinschaft, the Emergency Society for German Science. His most noteworthy contribution, although a failure, was to search the oceans for gold, in the hope of extracting enough to pay the war reparations demanded by the Allies. Nineteenth-century analyses had shown that some samples of seawater contained nearly twice as much as the lowest-grade land deposit that was profitable to operate. Unfortunately, Haber did not verify the published results, later established as much too high, and an extraction scheme was devised without ascertaining the exact amount of gold and its form in seawater. Several ocean trips were undertaken in vain, but a very accurate method for gold analysis was found.

Haber’s other activities during the postwar years proved more fruitful. His institute became one of the great scientific research centers in the world. During his tenure as director the Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry was credited with more than 700 publications in scientific journals. As at Karlsruhe and as head of chemical warfare, Haber showed himself to be a talented leader. He displayed versatility in handling a variety of subject matters in both academic and military situations. He was able to conform to a military environment and provide at other times a liberal and independent atmosphere to his associates. Beginning as an organic chemist, he contributed to every branch of physical chemistry as well as to peripheral sciences. He was a pure and applied scientist able to bridge the gap between the purist and the engineer. Men rather than accomplishments were the products of his direction; many outstanding physical chemists of the first half of the twentieth century started their careers with him.

The Haber Colloquium, a research seminar at his institute, began in October 1919 and soon attracted scientists from all parts of Europe. Haber’s contribution was clarity and the ability to abstract, spiced with satire and wit. His ability to think about and discuss material from the hydrogen atom to the flea, presented by expert lecturers, was greatly admired. As other commitments took him away from the meetings, they lost their verve and attendance dropped.

He was always engrossed in research projects and activities, and he had an extraordinary ability to concentrate, staying with problems both scientific and nonscientific. His speaking, reading, and writing habits were in this same mold. His best appreciated speeches were given at a commemoration for Justus Liebig, with whom he has been compared, and on the departure of his friend James Franck to join Göttingen University. He enjoyed mystery stories for recreational reading and composed verse for friends and relatives. He had an intellectual approach to these endeavors. Once he and Willstär planned a vacation based on biblical quotations. As a youth he was interested in dramatics, and throughout his life he showed a flair for the theatrical.

Haber served Germany well in his relations with foreigners and in foreign countries. His laboratories at Karlsruhe and Dahlem always had foreign students. In 1929 half of the sixty members of his Institute were foreigners from a dozen different countries. After World War I, the number or foreign visitors increased and he traveled to other countries for vacations and scientific meetings. After a two-month visit to Japan, he helped establish the Japan Institute for promoting mutual understanding and cultural interests. He represented Germany on the Board of the Union Internationale de Chimie from 1929 to 1933.

The Kaiser Wilhelm Institute was affected soon after the Nazis came to power. The Ministry of Art, Science and Popular Education demanded the dismissal of the Jewish workers there. Haber formally resigned in a letter dated 30 April 1933, writing: “For more than forty years I have selected my collaborators on the basis of their intelligence and their character and not on the basis of their grandmothers, and I am not willing for the rest of my life to change this method which I have found so good.”

Haber received an invitation to work at the Cambridge laboratory of William J. Pope, and he did so for four months. He also had an offer to head the physical chemistry section at the Daniel Sieff Research Institute in Israel and accepted, provided he found the climate and living conditions suitable. He died in Switzerland while on the way to the opening ceremonies for the Sieff Institute.

In 1935, on the first anniversary of his death, a number of learned societies in Germany did commemorate the occasion. Five hundred men and women gathered in Dahlem to pay tribute to him, despite the displeasure of the Nazis.

BIBLIOGRAPHY

I. Original Works. A full list of Haber’s works is in Morris Goran, The Story of Fritz Haber (Norman, 1967). His most important writings include “Bidioxymethylenindigo,” in Berichte der Deutschen chemischen Gesellschaft, 23 (1890), 1566, written with C. Liebermann; “über einige Derwate des Piperonals,” ibid.,24 (1891), 617; “Elektrolytische Darstellung von Phenyl-B-hydroxylamin,” in Zeitschrift für Elektrochemie, 5 (1898), 77–78; Uber die elektrische Reduktion von Nichtelektrolyten,” in Zeitschriftfür physikalische Chemie,32 (1900), 193–270; “über den textilen Flachdruck,” in Zeitschrift für angewandte Chemie and Zentralblatt für technische Chemie, 15 (1902), 1177–1183; and “Zur Theorie der Indigoreaktion,” in Zeitschrift für Elektrochemie, 9 (1903), 607–608.

See also “Über das Ammoniakgleichgewicht,” in Berichte der Deutschen chemischen Gesellschaft, 40 (1907), 2144–2154, written with R. Le Rossignol; “Zur Kenntnis des Hydroxylamins,” in Journal für praktische Chemie, 79 (1909), 173–176; “über die Darstellung des Ammoniaks aus Stickstoff and Wasserstoff,” in Zeitschrift für Elektrochemie, 16 (1910), 244–246; “Die Schlagwetterpfeife,” in Naturwissenschaften, 1 (1914), 1049; “Beitrag zur Kenntnis der Metalle,” in Sitzungsberichte der Preussischen Akademie der Wissenschaften zu Berlin (1919), 506–518; “Über amorphe Niederschäge and Kristal-lisierte Sole,” in Berichte der Deutschen chemischen Gesellscaft, 55 (1922), 1717–1733; and “Beitrag zur Kenntnis des Rheinwassers,” in Zeitschrift für anorganische and allgemeine Chemie, 147 (1925), 156–170, written with J. Jaenicke.

II. Secondary Literature. For works about Haber, see E. Berl, “Fritz Haber zum 60 Geburtstage,” in Zeitschrift für Elektrochemie, 34 (1928), 797–803; J. E. Coates, “The Haber Memorial Lecture,” in journal of the Chemical Society (Nov. 1939), pp. 1642–1672; M. Goran, “Present Day Significance of Fritz Haber,” in American Scientist (July 1947); and A. Stoll, ed., The Memoirs of Richard Willstätter (New York, 1965).

Morris Goran