{{short description|Irish X-ray crystallographer}} {{Use dmy dates|date=April 2022}} {{Infobox scientist | name = Helen Megaw | image = Helen Megaw.jpg | image_size = 153px | alt = Photo of Helen Megaw, wearing glasses and leaning over a piece of lab equipment | caption = Megaw circa 1950 | birth_date = {{Birth date|1907|06|01|df=y}} | birth_place = Dublin | death_date = {{Death date and age|2002|02|26|1907|06|01|df=y}} | death_place = Ballycastle, County Antrim | resting_place = | resting_place_coordinates = <!-- {{Coord|LAT|LONG|type:landmark|display=inline,title}} --> | residence = | citizenship = | father = Robert Megaw | fields = Crystallography | workplaces = | alma_mater = Queen's University, Belfast, Girton College, Cambridge | thesis_title = | thesis_url = | thesis_year = | doctoral_advisor = J. D. Bernal | academic_advisors = | doctoral_students = Robert E. Newnham<br>Sivaramakrishna Chandrasekhar | notable_students = | known_for = Crystallographer who determined the structure of ice crystals and the Perovskite crystal structure. | influences = | influenced = | awards = The Roebling Medal of the Mineralogical Society of America. Megaw Island and the mineral Megawite (CaSnO<sub>3</sub>) are named after her. | signature = <!--(filename only)--> | signature_alt = | website = | footnotes = | spouse = }} '''Helen Dick Megaw''' (1 June 1907 – 26 February 2002)<ref>A. M. Glazer, "Megaw, Helen Dick (1907–2002)", ''Oxford Dictionary of National Biography'' {{doi|10.1093/ref:odnb/76773}}</ref> was an Irish crystallographer who was a pioneer in X-ray crystallography.<ref name = "ulsterbio">{{Cite web | title = Helen Dick Megaw (1907 - 2002): Mineralogist | work = The Dictionary of Ulster Biography | accessdate = 2012-10-20 | url = http://www.newulsterbiography.co.uk/index.php/home/viewPerson/1919 }}</ref> She made measurements of the cell dimensions of ice and established the Perovskite crystal structure.
== Education and career == Megaw was born in Dublin to mathematics teacher Annie McElderry (1874-1968) and judge Robert Megaw, two graduates of Queen's University Belfast who were both originally from Ballymoney, Antrim.<ref>{{Cite journal |last=Glazer |first=Mike |date=2021 |title=Helen D. Megaw (1907–2002) and Her Contributions to Ferroelectrics |journal=IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control |volume=68 |issue=2 |pages=334–338 |doi=10.1109/TUFFC.2020.3035268 |issn=0885-3010|doi-access=free }}</ref> She was educated at first at Alexandra College in Dublin, and then briefly at Methodist College in Belfast after the family (including younger brother John, later a leading judge) moved back there in 1921, and finally at the Roedean School in England.<ref>[https://history.amercrystalassn.org/biography---megaw Helen Megaw] by Mike Glazer, American Crystallographic Association, 2018</ref> While still at school, Megaw read Bragg's ''X-rays and Crystal Structure.''<ref>{{Cite web |last=Coey |first=J. M. D. (Mike) |title=Megaw, Helen Dick |url=https://www.dib.ie/biography/megaw-helen-dick-a10386 |access-date=2025-02-19 |website=Dictionary of Irish Biography}}</ref> She spent a year at Queen's University, Belfast<ref name="ulsterbio" /> before moving to Girton College, Cambridge to study Natural Sciences in 1926. She graduated in 1930 and was a research student in crystallography under J. D. Bernal.<ref name = "ulsterbio"/> Megaw's first speciality was the structure of ice, and she was awarded her PhD in 1934,<ref name = "papers">''[http://janus.lib.cam.ac.uk/db/node.xsp?id=EAD%2FGBR%2F0271%2FGCPP%20Megaw Personal papers of Helen Megaw]''</ref> and Girton awarded her a Hertha Ayrton research scholarship which she used to study in Vienna in 1934-1935 under Hermann Francis Mark. In 1935 Megaw co-published with Bernal an influential method for fixing the position of hydrogen atoms known as the Bernal-Megaw model.<ref name="ulsterbio" /> She spent the year 1935–1936 in Oxford with Francis Simon<ref name="ulsterbio" /> and then spent several years as a schoolteacher before becoming an industrial crystallographer with Philips Lamps in London in 1943. It was through work at Philips on barium titanate that Megaw first worked on the perovskite crystal structure, on which she established herself as an acknowledged expert.<ref name="ulsterbio" /> In 1945 Megaw returned to working with Bernal, now at Birkbeck College in London, for a year before taking a post at the Cavendish Laboratory in Cambridge. She became a Fellow and Director of Studies at Girton. Megaw retired in 1972 and divided her time between Cambridge and Ballycastle, County Antrim, where she died in 2002.<ref name="ulsterbio" />
Her first book, ''Ferroelectricity in Crystals'', was published in 1957.<ref name="ulsterbio" /> It was followed by a second book, ''Crystal Structures: a Working Approach'', in 1973.<ref name="papers" />
Following a conversation with Mark Hartland Thomas in 1949 (chief industrial officer of the Council of Industrial Design), Megaw was appointed scientific consultant for the Festival Pattern Group of the Festival of Britain, 1951. She became the prime scientific mover in the group which put crystallographic images in the hands of industrial designers for them to use in products which were displayed at the Festival and in some cases beyond.<ref>{{Cite book|title=From atoms to patterns : crystal structure designs from the 1951 Festival of Britain : the story of the Festival Pattern Group|last=Lesley.|first=Jackson|date=2008|publisher=Richard Dennis|others=Wellcome Collection.|isbn=978-0955374111|location=Shepton Beauchamp|oclc=226282421}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=c3M3kdI5Xr4C&dq=megaw+festival+of+britain&pg=PA178|title=Guide to the Archive of Art and Design, Victoria & Albert Museum|last=Lomas|first=Elizabeth|date=2001|publisher=Taylor & Francis|isbn=9781579583156|language=en}}</ref> In 2019, some of Megaw's fabric samples were displayed at the Science Museum, London as part of an exhibition "The Art of Innovation"<ref>{{Cite book|last1=Blatchford|first1=Ian|title=The Art of Innovation|last2=Blyth|first2=Tilly|publisher=Transworld|year=2019|isbn=9781787632493|pages=216–225}}</ref> which explored the relationship between art and science.
== Legacy and honors == In recognition of her work in determining the structures of ice crystals, Megaw Island in the Southern Ocean is named for her.<ref>{{Cite web|url=http://cwp.library.ucla.edu/Phase2/Megaw,_Helen@851234567.html|title=Helen Megaw at the Contributions of 20th Century Women to Physics site.|archive-url=https://web.archive.org/web/20161006150409/http://cwp.library.ucla.edu/Phase2/Megaw,_Helen@851234567.html|archive-date=October 6, 2016|url-status=}}</ref> Megawite (CaSnO<sub>3</sub>), a perovskite-group mineral, is also named after her.<ref>{{Cite journal | volume = 75 | issue = 5 | pages = 2563–2572 | title = Megawite, CaSnO3: a new perovskite-group mineral from skarns of the Upper Chegem caldera, Kabardino-Balkaria, Northern Caucasus, Russia | journal = Mineralogical Magazine | date = October 2011 | doi = 10.1180/minmag.2011.075.5.2563 | bibcode = 2011MinM...75.2563G | last1 = Galuskin | first1 = E. V. | last2 = Galuskina | first2 = I. O. | last3 = Gazeev | first3 = V. M. | last4 = Dzierżanowski | first4 = P. | last5 = Prusik | first5 = K. | last6 = Pertsev | first6 = N. N. | last7 = Zadov | first7 = A. E. | last8 = Bailau | first8 = R. | last9 = Gurbanov | first9 = A. G. | s2cid = 130003129 }}</ref>
In 1976, Megaw gave a collection of fabric samples from the Festival of Britain along with a souvenir guide-book to the Science Museum in London.
In 1989, Megaw became the first woman to receive the Roebling Medal of the Mineralogical Society of America. She had honorary doctorates from the Universities of Cambridge and Queen's University Belfast.<ref name="ulsterbio" />
==Bibliography== * {{Cite book |last=Megaw |first=Helen D |title=Ferroelectricity in crystals |date=1957 |publisher=Methuen |location=London |language=English |oclc=2226235}} * {{Cite book |last=Megaw |first=Helen D. |title=Crystallographic Book List |date=1965 |isbn=978-1-4613-4620-3 |location=Boston, MA |oclc=913812505}} * {{Cite book |last=Megaw |first=Helen D. |title=Crystal structures: a working approach |date=1973 |publisher=Saunders |isbn=0-7216-6260-9 |location=Philadelphia |oclc=707007}} * {{Cite book |title=Historical atlas of crystallography |date=1990 |publisher=Published for International Union of Crystallography by Kluwer Academic Publishers |others=J. Lima-de-Faria, Martin J. Buerger, Jenny P. Glusker, Helen D. Megaw, Paul B. Moore, Marjorie Senechal, William A. Wooster |isbn=0-7923-0649-X |location=Dordrecht |oclc=20933210}}
==References== {{Reflist}}
== External links ==
* [https://collection.sciencemuseumgroup.org.uk/search/objects/object_type/textile-sample Megaw's collection of samples of fabrics inspired by crystallography from Festival of Britain; now at the Science Museum, London] * [https://collection.sciencemuseumgroup.org.uk/objects/co8084391/the-souvenir-book-of-crystal-designs-booklet "The Souvenir Book of Crystal Designs" from the Festival of Britain] {{Authority control}} {{Crystallography}}
{{DEFAULTSORT:Megaw, Helen}} Category:1907 births Category:2002 deaths Category:20th-century Irish women scientists Category:21st-century Irish women scientists Category:Irish women chemists Category:Crystallographers Category:Alumni of Girton College, Cambridge Category:Fellows of Girton College, Cambridge Category:Scientists from Dublin (city) Category:British crystallographers Category:Alumni of Queen's University Belfast Category:Academics of the University of Cambridge Category:People educated at Alexandra College Category:People educated at Methodist College Belfast Category:People educated at Roedean School, East Sussex Category:20th-century Irish chemists Category:Irish women physicists Category:20th-century women physicists Category:Women crystallographers