I began my path in computational chemistry while I still was an undergraduate student, working on my thesis under professor Cea at unam, synthesizing main group complexes with sulfur containing ligands. Quite a mouthful, I know. Therefore my first calculations dealt with obtaining Bond indexed for bidentate ligands bonded to tin, antimony and even arsenic; yes! I worked with arsenic once! Happily, I keep a tight bond (pun intended) with inorganic chemists and the recent two papers published with the group of Prof. Mónica Moya are proof of that.
In the first paper, cyclic metallaborates were formed with Ga and Al but when a cycle of a given size formed with one it didn’t with the other (fig 1), so I calculated the relative energies of both analogues while compensating for the change in the number of electrons with the following equation:
ΔE = E(MnBxOy) – nEM + nEM’ – E(M’nBxOy) Eq 1
A seamless substitution would imply ΔE = 0 when changing from M to M’
The calculated ΔE were: ΔE(3/3′) = -81.38 kcal/mol; ΔE(4/4′) = 40.61 kcal/mol; ΔE(5/5′) = 70.98 kcal/mol
In all, the increased stability and higher covalent character of the Ga-O-Ga unit compared to that of the Al analogue favors the formation of different sized rings.
Additionally, a free energy change analysis was performed to assess the relative stability between compounds. Changes in free energy can be obtained easily from the thermochemistry section in the FREQ calculation from Gaussian.
This paper is published in Inorganic Chemistry under the following citation: Erandi Bernabé-Pablo, Vojtech Jancik, Diego Martínez-Otero, Joaquín Barroso-Flores, and Mónica Moya-Cabrera* “Molecular Group 13 Metallaborates Derived from M−O−M Cleavage Promoted by BH3” Inorg. Chem. 2017, 56, 7890−7899
The second paper deals with heavier atoms and the bonds the formed around Yttrium complexes with triazoles, for which we calculated a more detailed distribution of the electronic density and concluded that the coordination of Cp to Y involves a high component of ionic character.
This paper is published in Ana Cristina García-Álvarez, Erandi Bernabé-Pablo, Joaquín Barroso-Flores, Vojtech Jancik, Diego Martínez-Otero, T. Jesús Morales-Juárez, Mónica Moya-Cabrera* “Multinuclear rare-earth metal complexes supported by chalcogen-based 1,2,3-triazole” Polyhedron 135 (2017) 10-16
We keep working on other projects and I hope we keep on doing so for the foreseeable future because those main group metals have been in my blood all this century. Thanks and a big shoutout to Dr. Monica Moya for keeping me in her highly productive and competitive team of researchers; here is to many more years of joint work.
Inorganic chemistry collaborations can be challenging with all those heavy elements, but at the same time also very fruitful and interesting, like yours. Congratulations to you and the rest of the team 🙂
Thank you! I thought I would meet you at WATOC. Maybe next time?
Thank you for sharing this Dr Barroso. Is there a simple way of saving computational time when running such a calculation with this number of atoms, more specially a calculation containing metals?
These were not computationally demanding since they are all closed shell. Metal containing compounds are not necessarily difficult to calculate unless you have spin-contamination.
Dear Dr. Barroso, how are you doing? The research group I work with is interested in studying certain organometallic complexes and we’re a little bit at loss in our search of the best way where to begin, could you give us a hint? We’re particularly confused regarding the input (or indications) one should give Gaussian: should one indicate the coordination number of the metal or another characteristic information? Is there literature you could recommend us to begin our journey?
We are experimental chemist who are practically new in the world of theoretical and computational chemistry.
You might remember me from a few months ago when I was having difficulties searching the transition state of taututomeric equilibriums.
Thank you in advance for your kind help.
María Fernanda Muñoz Pastori
Universidad Central de Venezuela (UCV)
Sure, please send me an email to jbarroso-at-unam-dot-mx
Inorganic chemistry is very easy for people if they provide solutions like yours but at the same time this article is very good and easy to understand things. Congratulations to you and your team who is providing value🙂