Category Archives: Random thoughts
Molecules. Atoms glued by bonds; nuclei incarcerated by electrons; electrons forming an inhomogeneous gas contained not by outer walls but by an electrostatic potential in its interior ironically named ‘external potential’. Molecules. The study object of chemists. The fundamental construct on which the chemical understanding of the universe relies.
Ten electrons, ten protons, and ten neutrons, giving rise to various electronic densities, various chemical properties: CH4, NH3, H2O, HF; which is it?
Atoms are letters, molecules are words; Chemistry, their unabashed poetry.
The format of a research paper hasn’t changed much throughout history, despite the enormous changes in platforms available for their consumption and the near extinction of the library issue. Convenient electronic files such as PDFs still resemble printed-and-bound-in-issues papers in their layout instead of exploiting the seemingly endless capabilities of the electronic format.
For instance, why do we still need to have page numbers? a DOI is a full, traceable and unique identification for each work and there are so many nowadays that publishers have to pour them out as e-first, ASAPs, and just accepted before having them assigned page numbers, a process which is still a concern for some researchers (and even for some of the organizations funding them or evaluating their performance). Numbers for Issues, Volumes and Pages are library indexes needed to sort and retrieve information from physical journals but in the e-realm where one can browse all issues online, perform a search and download the results these indexes are hardly of any use, only the year is helpful in establishing a chronological order to the development of ideas. This brings me to the next issue (no pun intended): If bound-issues are no longer a thing then neither should be covers. Being selected for a cover is a huge honor, it means the editorial staff think your work stands out from the published works in the same period; but nowadays is an honor that comes to a price, sometimes a high price. With the existence of covers, back-covers, inner-covers and inner-back-covers and whatnot at USD$1,500 a piece, the honor gets a bit diluted. Advertisers know this and now they place their ads as banners, pop-ups and other online digital formats instead of -to some extent- paying for placing ads in the pages of the journals.
I recently posted a quick informal poll on Twitter about the scientific reading habits of chemists and I confirmed what I expected: only one in five still prefers to mostly read papers on actual paper*, the rest rely on an electronic version such as HTML full text or the most popular PDF on a suitable reader.
— Joaquin Barroso (@joaquinbarroso) June 3, 2019
What came as a surprise for me was that in the follow up poll, Reference Manager programs such as Mendeley, Zotero, EndNote or ReadCube are only preferred by 15% while 80% prefer the PDF reader (I’m guessing Acrobat Reader might be the most popular.) A minority seems to prefer the HTML full text version, which I think is the richest but hardly customizable for note taking, sharing, or, uhm hoarding.
A follow up on the previous poll. Dear #ChemTweeps, if you mostly read papers in electronic format what is your preferred platform?
— Joaquin Barroso (@joaquinbarroso) June 10, 2019
I’m a Mendeley user because I like the integration between users, its portability between platforms and the synchronization features but if I were to move to another reference manager software it would be ReadCube. I like taking notes, highlighting text, and adding summaries and ideas onto the file but above all I like the fact that I can conduct searches in the myriad of PDF files I’ve acumulated over the years. During my PhD studies I had piles of (physical) paper and folders with PDF files that sometimes were easier to print than to sort and organize (I even had a spreadsheet with the literature read-a nightmarish project in itself!)
So, here is my wish list for what I want e-papers in the 21st century to do. Some features are somewhat available in some journals and some can be achieved within the PDF itself others would require a new format or a new platform to be carried out. Please comment what other features would you like to have in papers.
- Say goodbye to the two columns format. I’m zooming to a single column anyway.
- Pop-up charts/plots/schemes/figures. Let me take a look at any graphical object by hovering (or 3D touching in iOS, whatever) on the “see Figure X” legend instead of having to move back and forth to check it, specially when the legend is “see figure SX” and I have to go to the Supporting Information file/section.
- Pop-up References. Currently some PDFs let you jump to the References section when you click on one but you can’t jump back but scroll and find the point where you left.
- Interactive objects. Structures, whether from X-ray diffraction experiments or calculations could be deposited as raw coordinates files for people to play with and most importantly to download** and work with. This would increase the hosting journals need to devote to each work so I’m not holding my breath.
- Audio output. This one should be trickier, but far most helpful. I commute long hours so having papers being read out loud would be a huge time-saver, but it has to be smart. Currently I make Siri read papers by opening them in the Mendeley app, then “select all“, “voice“, but when it hits a formula, or a set of equations the flow is lost (instead of reading water as ‘H-Two-O‘, it reads ‘H-subscript Two-O‘; try having the formula of a perovskite be read)
- A compiler that outputs the ‘traditional version‘ for printing. Sure, why not.
I realize this post may come out as shallow in view of the Plan-S or FAIR initiatives, sorry for that but comfort is not incompatible with accessibility.
What other features do you think research papers should have by now?
* It is true that our attention -and more importantly- our retention of information is not the same when we read on paper than on a screen. Recently there was an interview on this matter on Science Friday.
** I absolutely hate having a Supporting Information section with long PDF lists of coordinates to copy-paste and fix into a new input file. OpenBabel, people!
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!
Mental health problems in graduate students have existed for ages. The constant and ever-increasing competition both in and out of the academic realm puts an extra toll on young students who already must deal with harsh economic conditions, an uncertain future, and the general unrecognition from society, not to mention sometimes a bullying environment from advisors. Back in the old days, struggling students were said to be ‘cracking under pressure‘, only for the heightening of thriving students who, in comparison, were deemed superior.
The story of Jason Altom is an extreme example of how a highly competitive environment may transform into an abusive one. Jason took his life in 1998 by ingesting potassium cyanide during his final years at Harvard. He was 26. The molecule he was trying to synthesize was completed the following year, and the corresponding report in JACS listed him as a co-author. It was also dedicated to his memory in the acknowledgements section. He was also not the first in the lab to take his life but his suicide note, as reported by The Crimson, suggested some policy changes like having not one but three supervisors per student.
Research institutions outside the top highest in the world, have also a lot of pressure put on students and young researchers even if the stakes are not Nobel-Prize-high. At the same time there are more graduate students now than ever before; the high demand for higher qualifications without the proper emotional development led to a critical mass of frustrated students who become bitter against the same activity they were first drawn to.
Getting a PhD, a real one, is tremendously hard, no question about it, but it shouldn’t be something you lose your mind for. Nothing should. One of my dearest mentors, Prof. Raymundo Cea-Olivares whom I’ve quoted many times before in this blog, often said that any human activity is hard, especially if you try to push its limits, yet PhD students are six-times more prone to suffer some kind of mental issue than a person the same age in the general population. To me, getting a PhD -or doing research for that matter- means you are trying to solve a question nobody else has been able to answer with methods you first need to master before even knowing whether they’re entirely suitable or not. A recurring theme in troubled students is not fully understanding what they are doing or why things are not going out the way they’re supposed to, which only increases the ‘impostor syndrome’ we all feel at some point or another. By definition, you are only an impostor if you’re working unethically, faking or stealing data, otherwise you’re welcome to my lab always; in fact, I prefer to deal with colleagues suffering from impostor syndrome than Dunning-Kruger‘s any day of the week. Here is the bottom line: superior or inferior its a relative term that only exists when you compare yourself to others. Don’t. Ever. The amount of time you devote to comparing yourself to others or indulging in self pity is wasted time you could well be using in doing something for yourself, whether it is studying, working or living.
If I should say something to struggling students is this: You are better than you think. That’s it. Seriously. You got into grad school and more importantly you will come out of it.
Nature has recently curated a collection of articles and essays addressing the mental-health problem in academia. Also, Prof. Christopher J. Cramer has a popular video on the matter, and somewhat tangentially so does Dr. Neil deGrasse Tyson. There are many other resources at your local university to help you cope with your PhD-derived anxiety, because remember: You are not alone.
I’ve lately reviewed a ton of papers whose titles begin with some version of “Computational studies of…“, “Theoretical studies of…” or even more subtly just subtitled “A theoretical/computational study” and even when I gotta confess this is probably something I’ve done once or twice myself, it got me thinking about the place and role of computational chemistry within chemistry itself.
As opposed to physicists, chemists are pressed to defend a utilitarian view of their work and possibly because of that view some computational chemists sometimes lose sight of their real contribution to a study, which is far from just performing a routine electronic structure calculation. I personally don’t like it when an experimental colleague comes asking for ‘some calculations’ without a clear question to be answered by them; Computational Chemistry is not an auxiliary science but a branch of physical chemistry in its own right, one that provides all the insight experiments -chemical or physical- sometimes cannot.
I’m no authority on authoring research papers but I encourage my students to think about the titles of their manuscripts in terms of what the manuscript most heavily relies on; whether it’s the phenomenon, the methodology or the object of the study, that should be further stressed on the title. Papers titled “Computational studies of…” usually are followed by ‘the object of study’ possibly overlooking the phenomenon observed throughout such studies. It is therefore a disservice to the science contained within the manuscript, just like experimental papers gain little from titles such as “Synthesis and Characterization of…“. It all comes down to finding a suitable narrative for our work, something that I constantly remind my students. It’s not about losing rigor or finding a way to oversell our results but instead to actually drive a point home. What did you do why and how. Anna Clemens, a professional scientific writer has a fantastic post on her blog about it and does it far better than I ever could. Also, when ranting on Twitter, the book Houston, we have a narrative was recommended to me, I will surely put it my to-read list.
While I’m on the topic of narratives in science, I’m sure Dr. Stuart Cantrill from Nature Chemistry wouldn’t mind if I share with you his deconstruction of an abstract. Let’s play a game and give this abstract a title in the comments section based on the information vested in it.
Communication of scientific findings is an essential skill for any scientist, yet it’s one of those things some students are reluctant to do partially because of the infamous blank page scare. Once they are confronted to writing their thesis or papers they make some common mistakes like for instance not thinking who their audience is or not adhering to the main points. One of the the highest form of communication, believe it or not, is gossip, because gossip goes straight to the point, is juicy (i.e. interesting) and seldom needs contextualization i.e. you deliver it just to the right audience (that’s why gossiping about friends to your relatives is almost never fun) and you do it at the right time (that’s the difference between gossips and anecdotes). Therefore, I tell my students to write as if they were gossiping; treat your research in a good narrative way, because a poor narrative can make your results be overlooked.
I’ve read too many theses in which conclusions are about how well the methods work, and unless your thesis has to do with developing a new method, that is a terrible mistake. Methods work well, that is why they are established methods.
Take the following example for a piece of gossip: Say you are in a committed monogamous relationship and you have the feeling your significant other is cheating on you. This is your hypothesis. This hypothesis is supported by their strange behavior, that would be the evidence supporting your hypothesis; but be careful because there could also be anecdotal evidence which isn’t significant to your own as in the spouse of a friend had this behavior when cheating ergo mine is cheating too. The use of anecdotal evidence to support a hypothesis should be avoided like the plague. Then, you need an experimental setup to prove, or even better disprove, your hypothesis. To that end you could hack into your better half’s email, have them followed either by yourself or a third party, confronting their friends, snooping their phone, just basically about anything that might give you some information. This is the core of your research: your data. But data is meaningless without a conclusion, some people think data should speak for itself and let each reader come up with their own conclusions so they don’t get biased by your own vision and while there is some truth to that, your data makes sense in a context that you helped develop so providing your own conclusions is needed or we aren’t scientists but stamp collectors.
This is when most students make a terrible mistake because here is where gossip skills come in handy: When asked by friends (peers) what was it that you found out, most students will try to convince them that they knew the best algorithms for hacking a phone or that they were super conspicuous when following their partners or even how important was the new method for installing a third party app on their phones to have a text message sent every time their phone when outside a certain area, and yeah, by the way, I found them in bed together. Ultimately their question is left unanswered and the true conclusion lies buried in a lengthy boring description of the work performed; remember, you performed all that work to reach an ultimate goal not just for the sake of performing it.
Writers say that every sentence in a book should either move the story forward or show character; in the same way, every section of your scientific written piece should help make the point of your research, keep the why and the what distinct from the how, and don’t be afraid about treating your research as the best piece of gossip you’ve had in years because if you are a science student it is.
Like everybody else, we are doing a brief recount of the achievements of this lab during 2016 if for no better reason because it helps me map my annual report.
We published seven articles:
- A Mixed DFT-MD Methodology for the In Silico Development of Drug Releasing Macrocycles. Calix and Thia-Calix[n]Arenes as Carriers for Bosutinib and Sorafenib Journal of Computational Chemistry 2016, 37, 10, 940–946
- In silico design of calixarene-based arsenic acid removal agents J Incl Phenom Macrocycl Chem (2016) 85:169–174
- Aromatization of pyridinylidenes into pyridines is inhibited by exocyclic delocalization. A theoretical mechanistic assessment Tetrahedron 72 (2016) 4194-4200
- Reactivity of electrophilic chlorine atoms due to σ-holes: a mechanistic assessment of the chemical reduction of a trichloromethyl group by sulfur nucleophiles Phys. Chem. Chem. Phys., 2016, 18, 27300-27307
- Ab Initio Modeling Of Friction Reducing Agents Shows Quantum Mechanical Interactions Can Have Macroscopic Manifestation J. Phys. Chem. A, 2016, 120 (46), pp 9244–9248
- Crystal Structure and DFT Studies of 4-Methyl-N-(1-phenylethyl)-N´-(1-phenylethylidene)benzenesulfonohydrazide. Evidence of a carbene insertion in the formation of acetophenone azine fromacetophenone p-toluensulfonyl hydrazone. Canadian Journal of Chemistry 2016 (doi: 10.1139/cjc-2016-0183)
- Synthesis and Crystal Structures of Stable 4-Aryl-2-(trichloromethyl)-1,3-diaza-1,3-butadienes Synthesis 2016, 48, 2205–2212
Two students got their degrees:
- María Eugenia “Maru” Sandoval got her Masters Degree with a thesis on mechanisms for the excitonic transference in photosynthetic pigments.
- Gustavo “Gus” Mondragón got his Bachelor of Sciences Degree also with a thesis on mechanisms for the excitonic transference in photosynthetic pigments.
And even a patent was filed! (more on that next year when appropriate.)
We participated in the annual Mexican Meeting on Theoretical Physical Chemistry with four posters and the internal symposium both at CCIQS and the Institute of Chemistry.
2016 was a great year for us and we hope to have an even better 2017 but just as before it will only be possible thanks to the hard work and dedication of all the members of this lab, -some of which have now left us to pursuit higher ends like Maru Sandoval who leaves for Spain and Guillermo Caballero who is already at Cambridge- and also to my colleagues who keep inviting us to collaborate in exciting projects. We have new members in the lab and also new research interests but the one common denominator throughout the years in the lab is fun; having fun in doing chemistry always.
Thank you to everyone who has ever read this blog and to those who have dropped a line here and there; I know I’ve neglected this space during this year, I want to fix it in 2017. May next year be awesome for everyone; lets make it so!
(Ah! Mathematicians, did you see what I did there?)
There are a number of appalling videos on line in which iPhones are destroyed by various means. From a chemist standpoint, the reason why I’m so disgusted with them is the waste of rare elements which go into the making of their components: From Neodymium to Indium, most of these metals come from conflict zones in which they are extracted in the most precarious conditions imaginable, but furthermore, they are so scarce the production of electronics is almost unsustainable. I wont post any links to these infuriating videos so as to not direct traffic to any of them, instead I will direct your attention to a wonderful book titled The Elements of Power: Gadgets, Guns, and the Struggle for a Sustainable Future in the Rare Metal Age by David S. Abraham. (Sheesh! Nobody uses short titles anymore? Can you imagine Nabokov writing Lolita: A little girl with a not so little mind and the professor who picked up on that? I digress.) It is hard not to read this long-titled book and feel a tad guilty; it is in fact a bit blackmailing but above all, realizing what a wasteful society (ugh! I hate that word) we are makes a strong wake up call to the future of sustainability. I would never claim that the solution is renouncing to technology but instead to find a sustainable technology within the framework of current technology. Easier said than done -of course- but stopping waste of such precious resources should be the first step in everyones mind, and don’t even get me started on balloons filled with He! In all fairness, one can also find a lot of scary articles on line from dubious to respectful on how smartphones and other rare-metals-containing gadgets are damaging the Earth.
Last year I enjoyed reading Andy Weir’s novel The Martian (later a major motion picture from Alien’s director Ridley Scott), in which an astronaut is stranded in Mars -left for dead by his crewmates, with nothing but the finite supplies of the station and his knowledge of chemistry, botany and engineering, all of which allows him to survive by extending, but above all reusing, those resources which included not only food but O2, H2O and even hydrazine, H2N2 originally intended for fuel but from where he now gets H2 for synthesizing a larger supply of water by reacting it with the O2 pulled out of the CO2-filled Martian atmosphere. I’m pretty sure Weir didn’t intend this novel to be a metaphor but it definitely works well as one of the limited resources available on Earth and the necessity of optimizing their use, collecting and disposal. Resources on Earth seem infinite, or they at least they did back when the industrial revolution started.
I guess the point is that sustainability goes hand in hand with using the least resources to get new ones as well as with avoiding their waste. I think one must agree that Chemistry, like no other science, has shaped our world for better and worse.
I haven’t rambled on sustainability in a while. Feels bad. Must be the winter.
In a nutshell, computational chemistry models are about depicting, reproducing and predicting the electronic-based molecular reality. I had this conversation with my students last week and at some point I drew a parallel between them and art in terms of how such reality is approached.
Semi empirical methods
Prehistoric wall paintings depict a coarse aspect of reality without any detail but nevertheless we can draw some conclusions from the images. In the most sophisticated of these images, the cave paintings in Altamira, we can discern a bison, or could it be a bull? but definitely not a giraffe nor a whale, most in the same way Hückel´s method provides an ad hoc picture of π electron density without any regard of the σ portion of the electron density or the conformational possibilities (s-cis and s-trans 1,3-butadiene have the same Hückel description).
More sophisticated semi-empirical Hamiltonians like PM3 or PM6 have better parametrizations and hence yield better results. We are still replacing a lot of information for experimental or adjusted parameters but we still cannot truly adopt it as truthful. Take this pre-medieval painting of one of the first Kings of England, Aelred the Unready. It is, by today standards, a good children´s drawing and not a royal portrait, we now see more detail and can discern many more features yielding a better description of a human figure than those found in Altamira or Egypt.
HF is the simplest of ab initio methods, meaning that no experimental results or adjustable parameters are introduced. Even more so, from the HF equations for a multi-electron system that complies with Pauli’s exclusion principle the exchange operator arises as a new quantum feature of matter with no classical analogue. Still, there are some shortcomings. Correlation energy is disregarded and most results vary according to the basis set employed. Take the impressionist movement, specially in France: In Monet´s Lady with Umbrella we have a more complicated composition, we observe many more features and although we have a better description of color composition some details, like her face, remain obscure. The impressionists are characterized by their broad strokes, the thicker the strokes the harder it is to observe details similar to what happens in HF when we change from a small to a large basis set, respectively.
CI (Configurations Interaction)
Extension of HF to a multi-reference method yields better results. In CI we take the original guess wavefunction -as expressed through a Slater Determinant- and extend it with one or many more wavefunctions; thus a linear combination of Slater Determinants gives rise to a broader description of the ground state because other electronic configurations are involved to include more details like the ionic and covalent pictures (configurations). The more terms we include the more real the results feel. If we take classical figurative paintings we have a similar result; most of these paintings are constituted of many elements and the more realistically each element is captured the more real the whole composition looks even if some are just merely indicated.
CCSD(T) full-CI, CASPT2
In Edwards Much’s the scream, we might think we have lost some information again and went back to impressionism but we know this is actually an expressionist painting; we can now not only observe details of the figurative portion of the image but Munch has captured his subject´s fear in the form of distorsions on the subjective reality. In this way, CCSD(T), full-CI and CASPT2 methods provide a description of the ground as well as the excited states which -in experimental reality- are only accessed through a perturbation of the elecron density by electromagnetic radiation. Something resembling radiation has perturbated the subject in The Scream rendering him frightened and wondering how to return to his ground state or if such thing will be even possible.
Density Functional Methods
At least due to its widespread use, DFT has risen as the preferred method. One of the reasons behind its success is the reduced computing time when compared to previous ab initio methods. So DFT is pretty much like photography, in which reality is captured in full but only apparently after selecting a given lens, an exposition, a filter, shutter speed and the occasional Photoshop for correcting issues such as aliasing. In photography, as in DFT, all details concerning the procedure or method for capturing an uncanny reproduction of reality must be stated in every case for reproduction purposes.
Now, in the end it all comes down to Magritte’s Pipe. Ceci n’est pas une pipe -or, ‘this is not a pipe’- reminds us that painting as with modeling we don’t get reality but rather a depiction of it. In this famous painting we look at an image that in our heads resembles that of a pipe but we cannot grab it, fill it with tobacco and smoke it.
The image above is a digital file, which translated becomes a scaled reproduction of an image painted by Magritte in which we see the 2D projection of the image of an object that reminds us of a pipe. In fact, the real name of this work is The Treachery of Images, definitely quite an epistemology problem on perception and knowledge but before I get too metaphysical I should finish this post.
Can you find where cubism or surrealism should be placed? with MPn methods, perhaps?
It was your idea. You had it. Or did it have you? But suddenly, you see it wrapped around someone else’s words. You read and gasp in denying shock. This can’t be! You read again trying to find your mistake, it is clearly a mistake on your part; to find it, you search for differences, preferably major ones that reveal that the identity of this idea is different to yours. You hope to just be mistaking it for yours. The wording is different, of course, you would have emphasized it differently, the way it deserved to be emphasized. But nevertheless its a mistreated version of yours. No matter what, this was yours. Was. Heartbroken, you try to save some face, by treating it differently; by treating it better!; by tending to those bits this third party is neglecting; by dumping it and getting a new and better one. You were so close. All in vain, for the fact is that this idea is no longer just yours, it seduced someone else’s mind and got brought to life by swifter hands. Now forever they will remain bound together as two celestial bodies are bound by gravity in the marriage of scientific annals, under the complicit auspice of editors and reviewers. Yes. You were the last to know this went on. It once made you feel so special, proud of your sparkling originality and your long hard work, brilliant even, but now you feel idle and exposed while in the dark.
You wish that at least you were perceived as a fool, as a laughing stock or even as an intellectual cuckold! But you are left worse than that: You are left with nothing. Empty handed. A runner up at best or part of the despised ‘me-too‘ kind, but only if you manage to get something out there at which the public scrutiny can roll their eyes. Still, that would be indeed better than having nothing to show for after all those long hours of shared intimacy with this idea. Angrily, you decide to blame others: technicians for delaying experiments; your collaborators for delaying revisions; your students for delaying data, and even the head of the department, maybe just for being other than yourself. You read again. The idea, no longer yours alone, stares back at you; no amount of hatred can change that. And then you wonder if you could have possible been on the other side before? You hope you have, for that means you are ahead in the game, but like in any game, sometimes you loose. Could your mind have been the seducing one before? You hope it has, for if it hasn’t it means you are playing alone in a corner of no interest to anyone, and what fun is that? What fun is a game in which you cannot win?
You mend fences. You accept that for this time someone was lucky but soon luck will come back and you will seduce other ideas; your hands will bring them to life and you will successfully collect the recognition for it, no matter how little the victory. Affairs with new ideas will come. Luck will come back. And it will come back to find you busily working or will not come back at all.