Category Archives: Talks
Density Functional Theory is by far the most successful way of gaining access to molecular properties starting from their composition. Calculating the electronic structure of molecules or solid phases has become a widespread activity in computational as well as in experimental labs not only for shedding light on the properties of a system under study but also as a tool to design those systems with taylor-made properties. This level of understanding of matter brought by DFT is based in a rigorous physical and mathematical development, still–and maybe because of it–DFT (and electronic structure calculations in general for that matter) might be thought of as something of little use outside academia.
Prof. Juan Carlos Sancho-García from the University of Alicante in Spain, encouraged me to talk to his students last month about the reaches of DFT in the industrial world. Having once worked in the IP myself I remembered the simulations performed there were mostly DPD (Dissipative Particle Dynamics), a coarse grained kind of molecular dynamics, for investigating the interactions between polymers and surfaces, but no DFT calculations were ever on sight. It is widely known that Docking, QSAR, and Molecular Dynamics are widely used in the pharma industry for the development of new drugs but I wasn’t sure where DFT could fit in all this. I thought patent search would be a good descriptor for the commercial applicability of DFT. So I took a shallow dive and searched for patents explicitly mentioning the use of DFT as part of the invention development process and protection. The first thing I noticed is that although they appear to be only a few, these are growing in numbers throughout the years (Figure 1). Again, this was not an exhaustive search so I’m obviously overlooking many.
The second thing that caught my attention was that the first hit came from 1998, nicely coinciding with the rise of B3LYP (Figure 2). This patent was awarded to Australian inventors from the University of Wollongong, South New Wales to determine trace gas concentrations by chromatography by means of calculating the FT-IR spectra of sample molecules (Figure 3), so DFT is used as part of the invention but I ignore if this is a widespread method in analytical labs.
While I’m mentioning the infamous B3LYP functional, a search about it in patents yields the following graph (Figure 4), most of which relate to the protection of photoluminescent or thermoluminescent molecules for light emitting devices; it appears that DFT calculations are used to provide the key features of their protection, such as HOMO-LUMO gap etc.
So what about software? Most of the more recent patents in Figure 1 (2018 – 2022) lie in the realm of electronics, particularly the development of semiconductors, ceramical or otherwise, so it was safe to assume VASP could be a popular choice to that end, right? turns out that’s not necessarily the case since a patent search for VASP only accounts for about the 10% of all awarded patents (Figure 5).
I guess it’s safe to say by now that DFT has a significant impact in the industrial development, one could only expect it to keep on rising, however the advent of machine learning techniques and other artificial intelligence related methods promise an accelerated development. I went again to the patents database and this time searched for ‘machine learning development materials‘ (the term ‘development’ was deleted by the search engine, guess found it too obvious) and its rise is quite notorious, surpassing the frequency of DFT in patents (Figure 6), particularly in the past 5 years (2018 – 2022).
I’m guessing in some instances DFT and ML will tend to go hand in hand in the industrial development process, but the timescales reachable by ML will only tend to grow, so I’m left with the question of what are we waiting for to make ML and AI part of the chemistry curricula? As computational chemistry teachers we should start talking about this points with our students and convince the head of departments to help us create proper courses or we risk our graduates to become niche scientists in a time when new skills are sought after in the IP.
Thanks again to Prof. Juan Carlos Sancho García at the University of Alicante, Spain, who asked me talk about the subject in front of his class, and to Prof. José Pedro Cerón-Carrasco from Cartagena for allowing me to talk about this and other topics at Centro Universitario de la Defensa. Thank you, guys! I look forward to meeting you again soon.
I’m very excited and honored to participate in this year’s Virtual Winter School on #CompChem. This event started back in 2015 and this year the list of participants includes Nobel Laureate and legend Roald Hoffmann. The topics will range from drug design to quantum chemistry on quantum computers. Additionally, two workshops will be given for ADF and Gaussian.
Aside from the teaching sessions there will also be some virtual social gatherings that promise to be a lot of fun. So don’t miss it next 21—25 of February 2022. Register here.
I will teach the tools to model Exciton Energy Transfer processes, a handy set of skills to work on the fields of photophysics, photosynthesis, or photochemistry of materials. We’ll review the concepts of excitons and the basic mechanisms by which they are originated and transferred.
Thanks to Henrique Castro from Rio de Janeiro for inviting me to be a part of this event which is a direct heir from the first electronic conferences organized by Profs. Bacharach and Rzepa. Here is the program.
It was my distinct pleasure for me to participate in the organization of the latest edition of the Mexican Meeting on Theoretical Physical Chemistry, RMFQT which took place last week here in Toluca. With the help of the School of Chemistry from the Universidad Autónoma del Estado de México.
This year the national committee created a Lifetime Achievement Award for Dr. Annik Vivier, Dr. Carlos Bunge, and Dr. José Luis Gázquez. This recognition from our community is awarded to these fine scientists for their contributions to theoretical chemistry but also for their pioneering work in the field in Mexico. The three of them were invited to talk about any topic of their choosing, particularly, Dr. Vivier stirred the imagination of younger students by showing her pictures of the times when she used to hangout with Slater, Roothan, Löwdin, etc., it is always nice to put faces onto equations.
Continuing with a recent tradition we also had the pleasure to host three invited plenary lectures by great scientists and good friends of our community: Prof. William Tiznado (Chile), Prof. Samuel B. Trickey (USA), and Prof. Julia Contreras (France) who shared their progress on their recent work.
As I’ve abundantly pointed out in the past, the RMFQT is a joyous occasion for the Mexican theoretical community to get together with old friends and discuss very exciting research being done in our country and by our colleagues abroad. I’d like to add a big shoutout to Dr. Jacinto Sandoval-Lira for his valuable help with the organization of our event.
I just came back from beautiful Cancun where I attended for the third time the IMRC conference invited by my good friend and awesome collaborator Dr. Eddie López-Honorato, who once again pulled off the organization of a wonderful symposium on materials with environmental applications.
Dr. López-Honorato and I have been working for a number of years now on the design application of various kinds of materials that can eliminate arsenic species from drinking water supplies, an ever present problem in northern Mexico in South West US. So far we have successfully explored the idea of using calix[n]arenes hosts for various arsenic (V) oxides and their derivatives, but now his group has been thoroughly exploring the use of graphene and graphene oxide (GO) to perform the task.
Our joint work is a wonderful example of what theory and experiment and achieve when working hand-in-hand. During this invited talk I had the opportunity to speak about the modeling side of graphene oxide, in which we’ve been able to rationalize why polar solvents seem to be -counterintuitively- more efficient than non-polar solvents to exfoliate graphene sheets from graphite through attrition milling, as well as to understand the electronic mechanism by which UV light radiation degrades GO without significantly diminishing there arsenic-adsorbing properties. All these results are part of an upcoming paper so more details will come ahead.
Thanks to Dr. Eddie López for his invitation and the opportunity provided to meet old friends and make new ones within the wonderful world of scientific collaborations.
The video below is a sad recount of the scientific conditions in Mexico that have driven an enormous amount of brain power to other countries. Doing science is always a hard endeavour but in developing countries is also filled with so many hurdles that it makes you wonder if it is all worth the constant frustration.
That is why I think it is even more important for the Latin American community to make our science visible, and special issues like this one from the International Journal of Quantum Chemistry goes a long way in doing so. This is not the first time IJQC devotes a special issue to the Comp.Chem. done south of the proverbial border, a full issue devoted to the Mexican Physical Chemistry Meetings (RMFQT) was also published six years ago.
I believe these special issues in mainstream journals are great ways of promoting our work in a collected way that stresses our particular lines of research instead of having them spread a number of journals. Also, and I may be ostracized for this, but I think coming up with a new journal for a specific geographical community represents a lot of effort that takes an enormous amount of time to take off and thus gain visibility.
For these reasons I’ve been cooking up some ideas for the next RMFQT website. I don’t pretend to say that my colleagues need any shoutouts from my part -I could only be so lucky to produce such fine pieces of research myself- but it wouldn’t hurt to have a more established online presence as a community.
¡Viva la ciencia Latinoamericana!
The RMFQT meeting is a long standing tradition within the Mexican Comp.Chem. community; a tradition that is now transcending our borders as more and more foreign students and researchers take part of this party, for it is a festive occasion indeed. This was the first time the RMFQT was held at a private institute, The Monterrey Institute of Technology.
As in previous years, our lab contributed with a four posters and one talk by yours truly. The posters presented by Raul Torres, Raúl Márquez, Gustavo Mondragón and Dr. Jacinto Sandoval whose pictures you can spot below in the gallery.
My talk was on the collaborative nature of Comp.Chem. and our particular interactions with the organic synthesis lab of Dr. Moisés Romero. The published papers discussed in the talk can be found in Tetrahedron (post), PCCP (post), and some unpublished results that can be read as a preprint in preprints.org.
I had the pleasure to meet and interact with old friends and make new ones like Dr. Julio Palma from Penn State, whose work on molecular rectifiers is very interesting. Also, I got to interact with many wonderful students who apparently are aware of the existence of this blog. (A big shoutout to M. Joaquina Beltrán and Plinio Cantero, from Chile whose work on DNA mismatch sensors is quite interesting, I look forward to further interacting with their team of research.)
A particular reason for this meeting to be special for me is the fact that I have been now announced as part of the local organizing committee for the next edition in 2019 in Toluca. I was also asked to develop a centralized website and coordinate the social media communication related to the this and other events, starting with the creation of the official Twitter account for our network and the meeting. I’m working on a few ideas, but if you have any suggestions please send them in the comments section.
See you next year in Toluca!
A yearly tradition of this Comp.Chem. lab and many others throughout our nation is to attend the Mexican Meeting on Theoretical Physical Chemistry to share news, progress and also a few drinks and laughs. This year the RMFQT was held in Puebla and although unfortunately I was not able to attend this lab was proudly represented by its current members. Gustavo Mondragón gave a talk about his progress on his photosynthesis research linking to the previous work of María Eugenia Sandoval already presented in previous editions; kudos to Gustavo for performing remarkably and thanks to all those who gave us their valuable feedback and criticism. Also, five posters were presented successfully, I can only thank the entire team for representing our laboratory in such an admirable way, and a special mention to the junior members, I hope this was the first of many scientific events they attend and may you deeply enjoy each one of them.
Among the invited speakers, the RMFQT had the honor to welcome Prof. John Perdew (yes, the P in PBE); the team took the opportunity of getting a lovely picture with him.
Here is the official presentation of the newest members of our group:
Alejandra Barrera (hyperpolarizabilty calculations on hypothetical poly-calyx[n]arenes for the search of NLO materials)
Fernando Uribe (Interaction energy calculations for non-canonical nucleotides)
Juan Guzmán (Reaction mechanisms calculations for catalyzed organic reactions)
We thank the organizing committee for giving us the opportunity to actively participate in this edition of the RMFQT, we eagerly await for next year as every year.
Last week the WATOC congress in Munich was a lot of fun. Our poster on photosynthesis had a great turnout and got a lot of positive feedback as well as many thought provoking questions. One of the highlights of my time there was seeing my former students and knowing they’re all leading successful and happy grad-student lives in Europe, I’m so very proud of them. It was great to connect with old friends and making new ones; a big thank you to all the readers of this little blog who took the time to come and say hi, I’m very glad the blog has been helpful to you.
Below there is an image of our poster (some typos persist).
See you all in 2020!
For the fifth year in a row my research group has participated in this traditional meeting on theoretical and computational chemistry, now at the beautiful city of Merida in southeastern Mexico.
Several distinguished international guests included Profs. Jose Luis Mendoza (Florida State University), Adrián Roitberg (University of Florida), Vincent Ortiz (Auburn University) and Paul Ayers (McMaster U. Canada); Their contributions rounded up nicely those of household names like Drs. Alberto Vela, Gabriel Merino (CINVESTAV) (the latter was also the main organizer), Jesus Hernández-Trujillo (UNAM), Jose Luis Gazquez (UAM-I), Óscar Jimenez (Guanajuato), and so many others who were also present.
My students presented four posters summarized below:
1) Maru Sandoval and Gustavo Mondragón on Photosynthesis, particularly the search for exciton transference mechanisms in both natural and theoretical arrangements of photosynthetic pigments. Some very exciting results have been observed; their publication is really near.
2) Raúl Torres and Gustavo Mondragón presented their work on arsenic removing calixarenes, published earlier this year, and the extension of said work to As(III) acids. Graphene oxide is now considered in our simulations as per the experimental work of our colleagues, Prof. Reyes Sierra and Prof. Eddie Lopez-Honorato.
3) Marco Diaz, Guillermo Caballero, Gustavo Mondragón and Raúl Torres had this poster on the calculation of sigma holes as descriptors for predicting pka values in organic acids. Their +1600 calculations project has found the best levels of theory (and ruled out some like B3LYP, of course) with some nice correlations. Yet, much work is still to be done but we’re on the right track.
4) Durbis Castillo presented his work on molecular docking and dynamics of a large library of HIV-1 entry inhibitors for which he uses the suite MAESTRO as a continuation of another project of ours. His enormous library is now in the hundredths of thousands and although we’re facing some technical difficulties, Durbis is thriving in his search. This is our first serious attempt towards a more mature drug discovery project; a manuscript should be ready in the first part of next year.
This guys and the rest of the lab who weren’t present are the ones who make our research flourish and they’ve all earned a day or two at the beach!
Here’s to fifteen more years of RMFQT!
Having a symposium right after the winter holidays is a great way to get back in touch with colleagues and students; we get to hear how their work is progressing and more importantly I get forced to become focused once again after a few weeks of just not paying much attention to anything related to work.
This year our group has happily gained some additions and sadly seen some others leave in search of a better future. María Eugenia “Maru” Sandoval gave a talk on the work she did on Singlet Fission (SF) in the Fenna-Matthews-Olson (FMO) complex during a three month stay at the Basque Country University in Spain under the supervision of Dr. David Casanova. Aside her calculations regarding Förster theory and a modification to Marcus’ equation, Singlet Fission was explored by her as a possible mechanism in which the Photosynthetic complex FMO might transfer solar energy from the antennae to the reaction center; one that might explain the high efficiency of it.
SF is a fascinating phenomenon: So you get an excited state S1 for a molecule1 that has been struck with a suitable photon; this excited state can either radiate back to the ground state (S0) but if there were two degenerate and coupled triplets whose energies are similar to half the S1 energy then the excited state might decay into [TT]1, hence singlet fission. In some cases (e.g. polyacene crystals) one of these triplets might be located in an adjacent molecule, this creates a hole in a second molecule due to the same single photon! This means creating twice the current albeit at half the voltage in photovoltaic materials. Maru has explored the possibility of SF occurring in natural systems and we think we might be on to something; she will defend her masters thesis any day now and we should see a publication later on this year. After that, she is pondering a few interesting options for her PhD.
On the poster session, our lab was represented by Marycarmen Reséndiz, Gustavo Mondragón and Guillermo Caballero. Durbis Pazos just now joined our group so he didn’t have to present a poster but nevertheless showed up gladly to support his colleagues. Gustavo will work on other aspects regarding the photochemistry of the FMO complex while Marycarmen is working on calculating the electronic interactions of chemically modified nucleotides when incorporated into DNA strands. Guillermo had a poster on his calculations for another reaction mechanism that caught his eye while still working with the experimentalists. I’m pleased to say that Guillermo is close to being published and also close to leaving us in order to get a PhD in a prestigious university that shall remain unnamed.
Thank you guys for keeping up the good work and maintaining the quality of the research we do, here is to a year full of success both in and out of the lab! Any success this lab has is due to you.