A success ☀️ American chemist Mario Molinaw

 Who was Mario Molina?

I attended fundamental faculty and high college in Mexico metropolis. i was already curious about technological know-how before entering high faculty; I still recall my pleasure once I first glanced at paramecia and amoebae via a as an alternative primitive toy microscope. I then transformed a lavatory, seldom used by the family, right into a laboratory and spent hours gambling with chemistry sets.

 With the help of an aunt, Esther Molina, who became a chemist, I endured with more challenging experiments along the strains of these completed by using freshman chemistry college students in college. preserving with our own family subculture of sending their youngsters overseas for multiple years, and aware of my hobby in chemistry, i was sent to a boarding school in Switzerland while i used to be eleven years old, on the assumption that German turned into an essential language for a potential chemist to analyze. I keep in mind i used to be pleased to go to Europe, however then i was upset in that my ecu schoolmates had no more hobby in technological know-how than my Mexican pals. 

I had already determined at that point to become a studies chemist; in advance, I had seriously pondered the possibility of pursuing a profession in track – I used to play the violin in those days. In 1960, I enrolled in the chemical engineering software at UNAM, as this became then the closest way to emerge as a physical chemist, taking math-orientated courses now not to be had to chemistry majors.

After completing my undergraduate studies in Mexico, I decided to get a Ph.D. degree in physical chemistry. It was no easy task; although my background in chemical engineering was good, it was weak in mathematics, physics and also in various areas of basic physical chemistry - subjects like quantum mechanics were completely foreign to me at the time.

 First, I went to Germany and enrolled at the University of Freiburg. After spending almost two years researching polymerization kinetics, I realized that I wanted to have time to study various core subjects to expand my knowledge and explore other areas of research. 

Therefore, I decided to pursue admission to a graduate program in the United States. While I was thinking about my plans for the future, I spent a few months in Paris, where I was able to study mathematics on my own and also had a great time discussing all sorts of topics, from politics, philosophy to art, etc. with many good friends. I subsequently returned to Mexico as an assistant professor at UNAM and established the first graduate program in chemical engineering. Finally, in 1968, I went to the University of California at Berkeley to pursue graduate studies in physical chemistry.

In my freshman year at Berkeley, I took physics and math classes in addition to the required physical chemistry classes. I then joined the research group of Prof. George C. Pimentel with the aim of using chemical lasers to study molecular dynamics, which his group discovered a few years ago.

George Pimentel also pioneered the development of matrix isolation techniques that are widely used in the study of the molecular structure and bonding of transient species. He was an excellent teacher and a great mentor; his warmth, enthusiasm and encouragement provided me with inspiration to tackle important scientific questions.

My graduate work involved research into the distribution of internal energy in the products of chemical and photochemical reactions; chemical lasers were well suited as tools for such studies. At the beginning, I had little experience with the experimental techniques needed for my research, such as handling vacuum lines, infrared optics, electronic instruments, etc. 

I learned a lot from my colleague and friend, Francisco Tablas, who was a postdoctoral fellow. time. Eventually I became confident enough to produce original results myself: my first success was in explaining some properties of laser signals - which at first appeared to be noise - as "relaxation oscillations", predictable from the basic equations of laser emission.

My years at Berkeley were some of the best of my life. I have just arrived after the era of the Free Speech Movement. I had the opportunity to explore many fields and engage in exciting scientific research in an intellectually stimulating environment. It was also during this time that I had my first experience of the impact of science and technology on society.

 I remember being concerned that high-powered chemical lasers were being used as weapons elsewhere; I wanted to be involved in research that was useful to society, not for potentially harmful purposes.

After finishing my Ph.D. degree in 1972, I stayed for another 12 months at Berkeley to maintain studies on chemical dynamics. Then, inside the fall of 1973, I joined the group of Professor F. Sherwood (Sherry) Rowland as a postdoctoral fellow, moving to Irvine, California. Sherry had pioneered studies on “hot atom” chemistry, investigating chemical residences of atoms with extra translational strength and produced by way of radioactive strategies. Sherry supplied me a list of research options: 

the only project that intrigued me the maximum consisted of locating out the environmental fate of sure very inert business chemical compounds – the chlorofluorocarbons (CFCs) – which had been gathering inside the atmosphere and which at that point were idea to have no large outcomes on the environment. This undertaking supplied me the opportunity to analyze a brand new subject – atmospheric chemistry – approximately which I knew little or no; seeking to solve a difficult hassle regarded to be an notable manner to plunge into a brand new research place.

 The CFCs are compounds similar to others that Sherry and that i had investigated from the point of view of molecular dynamics; we were acquainted with their chemical residences, however now not with their atmospheric chemistry.

three months after I arrived at Irvine, Sherry and that i evolved the “CFC-ozone depletion theory.” at the beginning the studies did no longer seem to be particularly exciting – I finished a scientific look for approaches that could smash the CFCs within the decrease surroundings, but not anything seemed to have an effect on them. We knew, however, that they might ultimately drift to sufficiently high altitudes to be destroyed by means of solar radiation. 

The query turned into no longer only what destroys them, however greater importantly, what the consequences are. We found out that the chlorine atoms produced by the decomposition of the CFCs would catalytically destroy ozone. We have become fully privy to the seriousness of the hassle whilst we as compared the economic quantities of CFCs to the quantities of nitrogen oxides which manipulate ozone tiers; the position of those catalysts of natural starting place had been established some years in advance via Paul Crutzen. We have been alarmed at the opportunity that the continuing release of CFCs into the atmosphere could purpose a big depletion of the Earth’s stratospheric ozone layer. 

Sherry and that i decided to change facts with the atmospheric sciences community: we went to Berkeley to confer with Professor Harold Johnston, whose work on the impact of the release of nitrogen oxides from the proposed supersonic delivery (SST) plane on the stratospheric ozone layer changed into widely known to us.

 Johnston knowledgeable us that months earlier Ralph Cicerone and Richard Stolarski had arrived at similar conclusions concerning the catalytic properties of chlorine atoms inside the stratosphere, in connection with the discharge of hydrogen chloride both from volcanic eruptions or from the ammonium perchlorate fuel deliberate for the gap commute.

We posted our findings in Nature, in a paper which regarded inside the June 28, 1974 issue. The years following the booklet of our paper were anxious, as we had determined to talk the CFC – ozone issue no longer best to different scientists, but also to policy makers and to the information media; we found out this was the handiest manner to insure that society would take a few measures to relieve the trouble.

To me, Sherry Rowland has continually been a exceptional mentor and colleague. I cherish my years of affiliation with him and my friendship with him and his wife, Joan. at the same time as he became on sabbatical leave in Vienna throughout the primary six months of 1974, we communicated via mail and smartphone. 

There had been many exchanges of mail during this short time frame, which illustrated the frantic pace of our research at that time while we endured to refine our ozone depletion concept. soon after, Sherry and that i posted several extra articles at the CFC-ozone problem; we presented our results at scientific meetings and we additionally testified at legislative hearings on capacity controls on CFCs emissions.

In 1975, i was appointed as a member of the school on the college of California, Irvine. although I persevered to collaborate with Sherry, as an assistant professor I needed to show that i was able to accomplishing unique research on my own.

 I hence installation an impartial software to investigate chemical and spectroscopic homes of compounds of atmospheric significance, focusing on the ones that are unstable and tough to address inside the laboratory, along with hypochlorous acid, chlorine nitrite, chlorine nitrate, peroxynitric acid, and so forth.

even though my years at Irvine had been very productive, I overlooked no longer doing experiments myself due to the numerous obligations related to a college function: teaching publications, supervising graduate college students, meetings, etc. 

After spending seven years at Irvine as Assistant and then partner Professor, I decided to move to a non-instructional role. I joined the Molecular Physics and Chemistry segment on the Jet Propulsion Laboratory in 1982. I had a smaller institution – only a few postdoctoral fellows – however I additionally had the luxurious of accomplishing experiments with my very own palms, which I enjoyed very a lot. certainly, I spent many hours within the laboratory in those years, engaging in measurements and developing techniques for the have a look at of newly emerging problems.

 round 1985, after becoming aware about the invention via Joseph Farman and his co-employees of the seasonal depletion of ozone over Antarctica, my research group at JPL investigated the abnormal chemistry which is promoted by means of polar stratospheric clouds, some of which encompass ice crystals.

 We had been capable to reveal that chlorine-activation reactions take area very effectively within the presence of ice beneath polar stratospheric situations; hence, we provided a laboratory simulation of the chemical outcomes of clouds over the Antarctic.

 also, if you want to recognize the rapid catalytic gas phase reactions that had been taking vicinity over the South Pole, experiments were done in my institution with chlorine peroxide, a new compound which had now not been suggested previously in the literature and which grew to become out to be vital in presenting the explanation for the rapid loss of ozone within the polar stratosphere.

In 1989 I back to instructional existence, moving to the Massachusetts Institute of technology, wherein i've persisted with studies on worldwide atmospheric chemistry troubles.

even though I now not spend a whole lot time within the laboratory, I very a good deal revel in operating with my graduate and postdoctoral students, who offer me with precious highbrow stimulus. i've additionally benefited from teaching; as I try to give an explanation for my perspectives to students with important and open minds, I find myself usually being challenged to go back and rethink thoughts. I now see teaching and studies as complementary, together reinforcing sports.

after I first chose the venture to investigate the fate of chlorofluorocarbons inside the surroundings, it became genuinely out of clinical interest. I did now not don't forget at that time the environmental outcomes of what Sherry and i had got down to examine. i am heartened and humbled that i used to be capable of do some thing that no longer only contributed to our know-how of atmospheric chemistry, however also had a profound effect on the global surroundings.

one of the very rewarding aspects of my work has been the interaction with a high-quality group of associates and friends within the atmospheric sciences community. I sincerely price these friendships, many of which go returned twenty years or greater, and which I assume to continue for lots more future years. I experience that this Nobel Prize represents popularity for the remarkable work that has been achieved with the aid of my colleagues and buddies within the atmospheric chemistry network at the stratospheric ozone depletion trouble.