Confirmed experimentally the ring structure of benzene , conjectured by Kekulé in 1865. She not only demonstrated the ring structure but showed that the molecule is planar and hexagonal - and gave its precise dimensions.

"Kathleen Lonsdale had a profound influence on the development of X-ray crystallography and related fields in chemistry and physics. Very few have made so many important advances in so many different directions."


-- J. M. Robertson, [dsb1981jr]

"As a physicist and mathematician by training, Kathleen Lonsdale's first major contribution was a profound and systematic study of the theory of space groups , methods for their determination, and the possibilities of molecular symmetry that are involved. This work was published with W. T. Astbury in 1924. ... A later continuation and extension of this work consisted of the structure factor tables published in 1936 ..., and the many volumes of the International Tables for X-Ray Crystallography published from 1952 onwards. These volumes, of which Kathleen Lonsdale was principal editor, are in constant use today and form an essential tool for crystal structure determination. " -- J. M. Robertson, ibid.

Work on physics of crystals:

"She made an intensive study of the magnetic anisotropy of crystals, and by measuring the diamagnetic susceptibilities in and perpendicular to the plane of a number of aromatic molecules, she was able to show that, while sigma electronic orbits were of atomic dimensions, the pi orbits were of molecular dimensions. The far reaching importance of this result was that it established the reality of the concept of molecular orbitals." -- ibid.

Demonstrated that diffuse X-ray reflection by single crystals is directly related to the elastic constants of the crystal and can be used to determine molecular orientation.

Development of divergent-beam X-ray photography of crystals:

"She was responsible for the development of divergent-beam X-ray photography of crystals, a technique which gives information about the texture and perfection of the crystal, and also can be used to make precise measurement of lattice constants or wavelength. By this means she was able to measure the C-C distance in individual diamonds to seven significant figures. She had a special interest in the structure of diamonds and made many other important contributions to their study."

-- J. M. Robertson, [dsb1981jr]

"The Structure of the Benzene Ring in Hexamethylbenzene," Proceedings of the Royal Society 123A: 494 (1929).

"An X-Ray Analysis of the Structure of Hexachlorobenzene, Using the Fourier Method," Proceedings of the Royal Society 133A: 536 (1931).

"Tabulated Data for the Examination of the 230 Space-groups by Homogeneous X-Rays," Philosophical Transactions of the Royal Society 224A: 221 (1924) with W. T. Astbury.

"Magnetic Anisotropy and Electron Structure of Aromatic Molecules," Proceedings of the Royal Society 159A: 149 (1937).

"An Experimental Study of Diffuse X-Ray Reflection by Single Crystals," Proceedings of the Royal Society 179A: 8 (1941).

"Diamonds, Natural and Artificial," Nature 153: 669 (1944).

"Divergent Beam X-ray Photography of Crystals," Philosophical Transactions of the Royal Society 240A: 219 (1947).

Texts

Simplified Structure Factor and Electron Density Formulae for the 230 Space Groups of Mathematical Crystallography, G. Bell & Sons, London, 1936.

Crystals and X-Rays, G. Bell & Sons, London, 1948.

International Tables for X-Ray Crystallography; vol. I (with N.F.M. Henry), vol. II (with J. Kasper), vol. III (with C.H. MacGillavry and G.D. Rieck; Kynoch Press, Birmingham; 1952, 1959, 1962.

Honors

Fellow of The Royal Society (London) 1945
The Society was founded in 1660. In 1945, Kathleen Lonsdale along with microbiologist Marjory Stephenson were the first women members elected.

Dame Commander of the Order of the British Empire 1956

Davy Medal of The Royal Society (London) 1957

General Secretary, British Association for the Advancement of Science 1959-64

Honorary Doctorates:
Universities of Wales, Leicester, Manchester, Lancaster, Leeds, Dundee, Oxford, and Bath.

Rare meteoric diamond was named Lonsdaleite in her honor.

1922-23 Research Assistant to William H. Bragg, University College, London
1923-27 Research Assistant to William H. Bragg, The Royal Institution, London
1927-30 Amy Lady Tate Scholar and part-time demonstratorship, Leeds University
(Between 1929 and 1934, Lonsdale gave birth to three children, and continued her research at home.)
1934 The Royal Institution
1935-37 Leverhulme Research Fellow, The Royal Institution, London
1944-46, Dewar Fellow, The Royal Institution, London
1946-49 Reader in Crystallography, University College, London.( Founded Crystallography Group.)
1947 Special Fellow of the United States Federal Health Service
1949-68 Professor of Chemistry and Head of the Department of Crystallography, University College, London
1968-71 Professor Emeritus, University College, London

B.S. Bedford College for Women 1922
M.S. University College, London 1924
D.Sc. University College, London 1936

References

[bmfrs1975dh], [dsb1981jr], [iss1970kl]

Additional Information/Comments

Lonsdale generously gave scientific assistance and encouragement to colleagues and coworkers. For example, she encouraged and assisted Nobel Laureate Dorothy Crowfoot Hodgkin in the work on the structure of penicillin, one of the discoveries which led to her Nobel Prize. Professor Hodgkin wrote about Dame Lonsdale [bmfrs1975dh]:

"..there are many of her interventions in scientific research that are unpublished, in the memories of all of us who knew and worked with her. One such, I should record, involved my own research. It was Kathleen Lonsdale who encouraged Sir Henry Dale to send to the Squibb Research Institute for sodium benzylpenicillin for my researches. And the first test of the X-ray microscope developed by W. L. Bragg and Charles Bunn was actually made at the Royal Institution by Kathleen Lonsdale herself to assist structure factor calculations for the penicillin crystals--a pilot operation which was later successfully extended in the actual X-ray analysis that defined the penicillin structure."

On the difficult task of balancing a career and family, Dame Lonsdale wrote:

"Sir Lawrence Bragg once described the life of a university professor as similar to that of a queen bee, nurtured, tended and cared for because she has only one function in life. Nothing could be farther from the life lived by the average professional woman." [iss1970kl].

A major priority for Lonsdale wa encouraging young people to enter science. She helped found the Young Scientists' section of the British Association for the Advancement of Science, and made the following note to herself: "Never refuse an opportunity to speak at schools." [bmfrs1975dh]

On women in science, Dame Lonsdale wrote:

"Any country that wants to make full use of all its potential scientists and technologists could do so, but it must not expect to get the women quite so simply as it gets the men. It seems to me that marriage and motherhood are at least as socially important as military service. Government regulations are framed to ensure (in the United Kingdom) that a man returning to work from military service is not penalized by his absence. Is it Utopian, then, to suggest that any country that really wants married women to return to a scientific career when her children no longer need her physical presence should make special arrangements to encourage her to do so?"[iss1970kl]

As a form of protest against World War II, Dame Lonsdale didn't register for civil defense duties and refused to pay the £2 fine. As a result, she was sentenced to one month in Hollaway Prison for Women. Lonsdale's first-hand experience made her a vocal advocate of prison reform. She was Member of Board of Visitors, Aylesbury Prison for Women and Borstal Institution for Girls; and Deputy Chairman of the Board of Visitors, Bullwood Hall, Borstal Institution for Girls.

She was a Quaker and an active spokesperson for world peace supporting the Pugwash Movement and serving as Vice-President of the Atomic Scientists Association and President of the Women's International League for Peace and Freedom.

She travelled extensively lecturing and attending meetings in over 25 countries.

Married Thomas Lonsdale in 1927 and they had three children - Jane, Nancy and Stephen.

A list of firsts:

First woman in 1945, along with microbiologist Marjory Stephenson, to be elected Fellow of The Royal Society (London).
First female professor, University College, London.
First woman president of the International Union of Crystallography (1966).
First woman president of the British Association for the Advancement of Science (1967).

Field Editor: Professor K. N. Trueblood