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Background of Dr Ronald James Gillespie
Name: Ronald James Gillespie
Birthdate: August 21,1924
Birthplace: London, England
Title: Professor Emeritus
Workplace: Department of Chemistry, McMaster University,Ontario,Canada
Status: Retired
Education:
BSc. University College London, 1945
PhD. University College London, 1949
DSc. University College London, 1957
CHILDHOOD
Figure 1: Ronald Gillespie in his childhood (Source: http://ronaldgillespie.weebly.com/)
Gillespie comes from poor family. Despite so, he is a hardworking and excellent student. At the age of 11, Gillespie received scholarship to the local grammar school. During high school, Gillespie was inspired by his chemistry teacher, Mr. George Cast. Mr. Cast always make chemistry seem to be more exciting compared to textbook by doing lab experiments with his students. Ronald Gillespie specialized in chemistry, physics, and pure and applied mathematics, but did particularly well in chemistry. Gillespie left school in 1942.
UNIVERSITY LIFE
He was awarded a bursary to do a special two year wartime degree at University College London.
During second year, he began to join research group and pursue his studies in sulfuric acid, taking his research in a new innovative direction. This led to the quest to discover other super acid systems of even greater acidity. In 1949,he was already appointed as an assistant lecturer before awarded his Ph.D by University College London. In 1953 Gillespie was awarded a Commonwealth Fund Fellowship. Gillespie moved to McMaster University in Hamilton, Ontario in 1958. The offer from McMaster double his salary and gave him the chance at research funding from the National Research Council of Canada.
WORKING EXPERIENCE
Dr. Ronald J Gillespie had hold numerous faculty positions and are so experienced. The list of working experience can be seen below. (Adapted from: http://ronaldjg.weebly.com/education-and-career.html)
1948 - 1950: Assistant Lecturer, Department of Chemistry, University College London.
1950 – 1958: Lecturer, Department of Chemistry, University College London.
1958 – 1960: Associate Professor, Department of Chemistry, McMaster University, Hamilton, Canada.
1960 – 1989: Professor, Department of Chemistry, McMaster University, Hamilton, Canada.
1962 – 1965: Chairman Department of Chemistry, McMaster University, Hamilton, Canada.
1989 : Present Emeritus Professor, McMaster University, Hamilton, Canada.
Figure 3: McMaster University where Gillespie work and continue his research. (Source: wikimedia.org)
AWARDS
Gillespie recieved many awards for his contribution. Below is the award received according to year. (Adapted from: http://rjgillespie.weebly.com/awards-and-achievements.html)
1953: Fellow of the Royal Institute of Chemistry
1960: Fellow of the Chemical Institute of Canada
1965: Fellow of the Royal Society of Canada
1966: Noranda Award (Chemical Institute of Canada),
1967: Canadian Centennial Medal,
1976: Union Carbide Award (Chemical Institute of Canada) for Chemical Education,
1977: Silver Jubilee Medal,
1977: Chemical Institute of Canada Medal,
1977: Fellow of the Royal Society, London,
1983: Tory Medal (Royal Society of Canada)
2007: Order Of Canada
According to Brian McCarry, chair of the Department of Chemistry, Order of Canada recognizes Ron Gillespie's pioneering research in main-group inorganic chemistry, particularly in the areas of fluorine chemistry, super acid media and concepts of chemical bonding. In addition to his research, Gillespie is also claimed to be popular for his talent as lecturer and educator.
"Dr. Gillespie has made a tremendous impact on science and the Faculty of Science continues to benefit from his contributions and influence in teaching and research within the field of chemistry," said John Capone, dean of the Faculty of Science. "We are proud of him and his accomplishments and are delighted with his appointment to the Order of Canada."(Source: http://dailynews.mcmaster.ca/)
Figure 4: Order of Canada is given to those who make a major difference to Canada through lifelong contributions . (Source: wp.rac.ca)
PUBLICATION
Dr. Ronald J. Gillespie published some books and journal articles. (Source:ttp://www.chemistry.mcmaster.ca/gillespie/)
1. Molecular Geometry, Van Nostrand Reinhold, London, 1972, 226 pages.
German translation: Verlag Chemie 1975
Russian translation: MIR 1975
2. Chemistry, with D.A. Humphreys, N.C. Baird and E.A. Robinson
3. The VSEPR Model of Molecular Geometry (Figure 5) with I. Hargittai Allyn and Bacon, 1991
Russian translation: MIR 1992
Italian translation Zanichelli 1994
Figure 5: The VSEPR Model of Molecular Geometry (Source:http://ronaldjg.weebly.com/)
4. Atoms, Molecules and Reactions: An Introduction to Chemistry (Figure 6) with D.A. Humphreys, E.A. Robinson and D.R. Eaton,
Prentice Hall, 1994, 750 pages.
Figure 6: Atoms, Molecules and Reactions: An Introduction to Chemistry (Source:http://ronaldjg.weebly.com/)
A new book is to be published by Oxford University Press in 2001:
5. The Chemical Bond and Molecular Geometry: from Lewis to Electron Densities.
by Ronald J. Gillespie and Paul L. A. Popelier
Journal Articles
Gillespie has over 370 articles in: The Journal of the American Chemical Society (ACS), Inorganic Chemistry, The Canadian Journal of Chemistry, The journal of the Chemical Society, The Journal of Chemical Education, and many others.
AREA OF INTEREST
Dr. Ronald James Gillespie has made many crucial contribution in Chemistry field. His major contribution such as:
Study of Noble gas Fluorofication BLOG TIPS: Click the title and and pick contribution part to read on that particular topic or simply scroll down.
VSEPR THEORY
Valence Shell Electron Pair Repulsion or VSEPR Theory is a method to determine the geometry of a molecule based on the idea that electron pairs are as far apart as possible. It is also known as Gillespie-Nyholm theory as it was developed by the two great chemist. Firstly, the idea of correlation between molecular geometry and number of valence electrons (both shared and unshared) was originally proposed in 1939 by Ryutaro Tsuchida in Japan. In 1957, Gillespie done extensive work on expanding the idea of the Valence Shell Electron Pair Repulsion (VSEPR) model of Molecular Geometry, which he developed with Ronald Nyholm, and setting the rules for assigning numbers. Their contribution defined VSEPR theory in more detailed concept and we are able to choose between alternative geometry.
Video1: Brief explanation on VSEPR theory. (Source: Youtube.com)
Electron pairs in the valence shell of a central atom can be determined by drawing the Lewis structure of the molecule, and expanding it to show all bonding groups and lone pairs of electrons
Figure 1: Drawing Lewis structure can determine the shape of the molecule according to VSEPR theory. (Source:http://chemed.chem.purdue.edu/)
AXE notation also used when applying VSEPR theory. A is the central atom which always has 1 subscript. X is the number of sigma bond between central and outside atoms. E is the number of lone electron pairs surrounding the central atom. Sum of X and E is known as steric number. VSEPR theory uses steric number and distribution of X's and E's to predict molecular geometric shape as figure 2 below.
Figure 2: AXE method annotation, geometry and example for each shape. (Source: https://www.boundless.com/)
Limitation of VSEPR Theory
Like other theory, VSEPR theory also has exceptions and limitations. The limitations are for:
Isoelectronic species.
Isoelectronic species are elements, ions and molecules that share same number of electrons. Although two isoelectronic compound have the same number of electrons, but it has different geometry shape. For example, VSEPR predict the shape of IF7 and [TeF7]- that have 56 electrons to be pentagonal bipyramidal. However, the equatorial of F atoms in [TeF7]- are not coplanar according to X-ray diffraction. Thus, VSEPR fails to predict it shape.
Transition metal compounds.
As VSEPR theory does not take relative sizes of the substituents and stereochemically inactive lone pairs into account, it fails to predict structure of certain compound. For example,[TeCl6]2-is predicted to have pentagonal bipyramidal geometries according to VSEPR since the central atom can have seven electron pairs. However, due to the stereochemical inert pair effect, these molecules are found to be regular octahedral because one of the electron pairs is stereochemically inactive. The shape can be seen in figure 3 below.
Figure 3: Transition metal that disobey VSEPR theory. (Source: http://chemwiki.ucdavis.edu/)
REASONS CONTRIBUTION IS CRUCIAL
VSEPR theory can determine the shape of molecule. This is important to understand the reaction and properties. Properties like smell, taste and proper targeting of drugs are all possible because of knowing the shapes of molecule. VSEPR theory also a great predictive tool that make it simple for student to understand element's molecular geometry. Scientist no longer need to depends on X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy to know the 3-D structure of molecule.
Figure 4: X-ray crystallography determine the atom arrangement(Source: http://chemwiki.ucdavis.edu/)
MODIFICATION ON THE CONTRIBUTION
Kepert Model is the modification of VSEPR theory. It able to predict the molecular geometry shape of transition metal. Since transition metal have partially filled d-subshells, VSEPR theory doesn't work for them. The different between Kepert model and VSEPR theory is Kepert model does not account for non-bonding electrons and it considered ligands attached to the metal repel each other like point charges repel each other in VSEPR theory. Here is the coordination numbers and geometries of Kepert model. (click to enlarge)
Figure 5: Shape of molecule is determined by the coordination number in Kepert model. (Source:http://www.unf.edu/)
Example, the d8 metals like Ni(II), Pd (II), Pt (II), Au (III) and d9 metals like CU(II) has square planar shape. Figure below shows the geometry of Platinum transition metal.
Figure 6: The isomer of platinum (II) which has the shape of square planar. (Source:http://www.unf.edu/)
Here is the geometry of Rhenium, Re a third row transition metal in group 7 according to Kepert model. Rhenium has 6 coordination number with geometry of trigonal prismatic.
Figure 7: The less common arrangement of rhenium. (Source:http://www.unf.edu/)
The limitation for Kepert Model is it cannot explain the formation of square planar complexes or distorted structures.
IS IT WIDELY ACCEPTED?
VSEPR theory is widely accepted. This is obvious in medical field. For example, shape of Aspirin is important to be determined as the shape affect the pain. Aspirin act as inhibitor that will bind at the reactant side to block the substrate which cause pain from binding. If the molecular shape of the medicine does not portable, the medicine will not be effective to the pain. This is explained in figure 4 below.
Figure 8: Aspirin blocking substrate from binding to enzyme which consequently avoid inflammation. (Source:www.sjaweb.org )
FUTURE CHEMISTRY VSEPR theory is important whether now or in the future. If a chemists found a new element, they can simply determine it properties by analyzing the shape. This can be done with the present of VSEPR theory. In the future, VSEPR theory need to be modified until there is no limitation. VSEPR theory should be modified to become better than the current model. So that, the VSEPR model can predict for the entire element including for transition metal compound and isoelectronic compound.
SUPERACID
Superacid is acid with acidity greater than that of 100% pure sulfuric acid. It is a medium with chemical potential of proton is higher than in pure sulfuric acid. Strong superacids can be prepared by combining strong Lewis acid and a strong Brønsted acid.
Professor Gillespie's investigations into superacid media began with his Ph.D. research under the supervision of C.K. Ingold at London University. He first discovered superacid when he wants to demonstrate the formation of the nitronium ion, NO2+, upon dissolution of nitric acid in sulfuric acid.
Video 2: Superacids are much stronger than sulfuric acid.(Source: youtube.com)
Example of superacids are Fluoroantimonic acid, (H2FSbF6) which is made by combining hydrogen fluoride (HF) antimony pentafluoride (SbF5). Fluoroantimonic acid is 1016 times stronger than 100% sulfuric acid. The shape of fluoroantimonic acid is shown in figure 9.
Figure 9: Molecular geometry of Fluoroantimonic acid. (Source:https://en.wikipedia.org/wiki/Fluoroantimonic_acid)
REASONS CONTRIBUTION IS CRUCIAL
Superacid has a great potential applications in fuel cell technology, chemical and petroleum industries. Development of superacid is important for the generation. Superacids able to break hydrocarbons into positively charged hydrocarbon cations or also know as carbocations. This able the hydrocarbon to be transform into another useful form, like plastic while giving out carbocations as intermediates. Development of superacids also leads to production of non-metallic elements in the form of polyatomic cations which will be discussed next.
MODIFICATION ON THE CONTRIBUTION
In 1960, George Olah has developed the Magic Acid. Magic acid is a superacid with mixture of fluorosulfuric acid (HSO3F) and antimony pentafluoride (SbF5). Magic acid was discovered after a Christmas party held by the group of Professor George Olah, when a student found that a left-over candle dissolved completely in a magic acid solution.Hydrocarbon is poor proton acceptor but it dissolved in extreme acidity of magic acid. Professor Olah used this superacid in his innovative research of carbocation chemistry, and became the sole recipient of the Nobel Prize in Chemistry in 1994.
Figure 10: George A. Olah, chemist that was born in Budapest, Hungary. (Source: http://www.nobelprize.org/)
IS IT WIDELY ACCEPTED?
When Gillespie first discover the acid, they proposed to call these solutions "superacid solutions." Their proposal was, however, not further followed up or used until the 1960s, when Olah's studies of obtaining stable solutions of highly electron-deficient ions, particularly carbocations, focused interest on very high-acidity nonaqueous systems. Subsequently, Gillespie proposed an arbitrary. Since then widely accepted definition of superacids are any acid system that is stronger than 100% sulfuric acid.
Now, superacids is widely accepted as it brings a lot of advantages. One of the example; in petrochemistry, superacidic media are used as catalysts. Typical catalysts are sulfated oxides of titanium and zirconium. The solid acids are used for alkylating benzene with ethylene and propylene as well as difficultacylations.
In addition, superacid can also use for daily or periodical removal of milk stone calcareous residues in milking plants, cooling tanks and pipes. Its use is also specific for beer scale removal from tanks, capacitors, kegs, automatic washing and dosing plants. it can treated surface like floors and tile walls, epoxy resin surfaces, stainless steel surfaces and pipes, stainless steel plants, and stainless steel grills.
Figure 11: Superacid has many commercial uses especially in the industry fields. (Source: http://www.maber.com/products/0099-superacid.html)
FUTURE CHEMISTRY
In the future, superacids should be used widely in catalytic application as gives lot of advantages like less by-products and lower the reaction temperature. Modification of superacids are on going and hopefully there are a lot application of superacids in the next few years.
POLYATOMIC CATIONS
Superacid leads to the discovery of
many polyatomic cations of non metal. Using the modern physicochemical and
spectroscopic tools,Gillespie and co-workers were quick to characterize
the newly identified species. This has extended their chemistry far beyond
what is possible in aqueous solution. The first evidence of the
polyatomic nature of the I2+ and I42+ species,
was provided by Gillespie. Other exotic species prepared by Gillespie are Br2+,
Br3+, S42+, S82+,
S192+, Se42+, Se102+,
Te42+, Te62+and Te4Se42+,
both in solution and in crystalline salts. Structure of these species are
determined using X-ray crystallography and extended our understanding of
chemical bonding. This is really great as the only common polyatomic cation we usually head are such as mercury, Hg22+ ammonium, NH4+ and hydronium,H3O+. Below is figure of polyatomic ammonium cation.
Figure 12: 2D skeletal version of ammonium ion. (Source: en.wikipedia.org)
RELATION TO COURSE
Ronald J Gillespie contribution in both VSEPR theory and superacid gives significant impact to me. Through the VSEPR theory, I'm able to imagine how a molecule shape look like and how to draw them. By knowing their shape also, I can know how would they react, their character and properties such as smell and polarity of the molecule. I also noted that even some molecule have same valence electron, they have different molecular geometry.
In addition, the discovery of superacid by Ronald J Gillipsie makes me realize there is stronger acid than 100% sulfuric acid. It is crucial fr us to acknowledge the difference between superacids and strong acid as it is a vital part in the chemical industry.
CONCLUSION
All in all, we should appreciate Dr. Ronald J. Gillespie contribution in the chemistry field. Without his findings and research we may be lack of useful and precise information that is vital in our life. We should take Dr. Ronald J. Gillespie as a role model as he is very hardworking person. At the age of 91, after retiring, he still continue his research on VSEPR theory. This unstoppable attitude and determination is what we should follow. If there is a lot of people like this Canadaian chemist, Dr. Ronald J. Gillespie, we will live better modernized future.
Extra.
Here are some wise quotes from Ronald J Gillespie and fun facts about him. (Click to enlarge image)
Fun Facts
He was a skier, and a sailor
He is always looking for fresh explanations for how things work, he is always open for alternate explanations.
Even though he is retired, he still researches his VSEPR model.
He felt it was his responsibility to improve the effectiveness of teaching.
His textbooks are used widely in freshman chemistry, even today.
Hello, I'm agent 099 on secret mission #1.This is the result of my research, relating Canadian chemist,Dr. Ronald James Gillespie. All the information here is private.
Polaroid picture - Profile
Paper clips - Contribution
Magnifying glass - References
Compass - Extra
Study of Noble gas Fluorofication
Isoelectronic species.
He was a skier, and a sailor
He is always looking for fresh explanations for how things work, he is always open for alternate explanations.
Even though he is retired, he still researches his VSEPR model.
He felt it was his responsibility to improve the effectiveness of teaching.
His textbooks are used widely in freshman chemistry, even today.
