Giuliana Materzanini

Giuliana did her undergraduate and master’s studies in Theoretical Physical Chemistry at La Sapienza University in her hometown of Rome. After completing her master’s thesis on molecular collisions in the gas phase within the group of Prof. Gianturco, she switched to solid state physics during her PhD on the growth of copper thin films and water adsorption on ruthenium surfaces from a theoretical point of view, at the University of Milan (Prof. Tantardini) and University College London (Prof. Saalfrank). She had started a second postdoc at the University of Milan when she became pregnant with her second child. Though she didn’t plan to leave research at the time, integrating her personal and professional lives became too complicated and she spent the next 12 years as a full-time mother. Though she had never thought about re-entering research, she had a revelation about three years ago and decided to explore the possibilities. She met Nicola Marzari at a conference in Copenhagen and has been a post-doc in his group since February 2017.

Interview by Carey Sargent, EPFL, NCCR MARVEL

The biggest challenge women scientists face is...

I believe that society is changing slowly and it's still a matter of fact that many works are gender-biased, like for instance secretary jobs are much more populated by women and science jobs by men. In science women disappear mostly after completing their PhDs, more or less like it happened to me. One evident reason for this is that society “is not ready yet” to treat men and women at the same level, at least when they grow a family. But this is not the only issue, and there are many other reasons on which we can and should work hard, both women and men. One (maybe straightforward) issue for a woman is to find the right partner, that should like her as a person and respect her to the end. Respect should be seen in facts. Like understanding when work, also for a woman, has to come before the family, or feeling responsible for the children, also for little things like waking up early in the morning and taking them to school. I have seen nice couples that were really great with that. For me that was always hard. Then there are bosses and colleagues – I have been very lucky, but unfortunately gender-based biases exist in many sectors, and – sad to say – even in science. We shouldn't pretend not to see them, when they are there. Ultimately, there is also the idea that you have about yourself. A PhD student recently told me that she didn't think important to highlight women-in-science problems, as she didn't feel herself less intelligent than men. I answered that I was happy for her, but at the same time, being 20 years older, I take nothing for granted and I find absolutely important that women scientists constantly interrogate themselves about their self-determination. Gender biases exist, both in women's and men's minds, and the first step towards improving this is to be aware of it.

If I weren’t a scientist, I would be…

I actually had a passion for philosophy before starting my chemistry studies and, really up to the last moment, I was sure that I would have gone to philosophy. But when I saw the study plan in Rome I felt it was too much like becoming a journalist, whereas what I wanted was to study the human brain, to discover the laws of logics and to learn to formulate my own answer to the eternal question “Why are we here?”. I am still very interested in the topic – I believe that mathematics, physics and even chemistry are profoundly connected with philosophy, and a lot of philosophers were scientists. Actually I could have also been a teacher in (high) school. I like to teach a lot. I don't agree with the opinion that teaching should be worth more in academia than in high school, because in a way teaching to a semi-expert audience can be much easier than explaining something very complicated to an audience of non-expert (sometimes not enough motivated) people. I enjoyed teaching for four months in an elementary school and I learned that teaching to young children can be very challenging!

Most exciting MARVEL discovery…

My work is using first-principles theories to study the properties of materials, in particular of the so-called superionic materials, that are ionic solids showing considerable transport (i.e. liquid-like behavior) for a certain ions subnetwork, whereas the rest of the crystal behave like a solid. These materials, though discovered already 150 years ago, have become popular only in the last 40 years, thanks to the advent of the Li-ion batteries, for which they could serve as electrolytes, eventually enabling a safer-batteries market and, ultimately, the realization of green-energy strategies. My first work in these two years of post-doc has led me to discover that an oxide, that was believed so far not to be interesting from the point of view of the ionic conductivity, is instead a good ionic conductor if synthesized in a certain phase. But the real challenge now is to prove that this phase can be obtained experimentally and to point out a synthesis route to achieve this, in close collaboration with our experimental Marvel counterparts, especially Dr. Claire Villevieille. Discoveries in science can be like an explosion, but I think it is more common that they come little by little, and one has to be persevering, never giving up with an idea, if one really believes it. On my desk I have a postcard that says “L'important c'est d'y croire”!

My top two papers…

Among my own papers, my favourite one is about water adsorption at the Ru(0001) surface. It's a Physical Review B that was published in 2005, right after when my daughter was born. Though it has been my best paper so far, it sadly marked a partial end of my career, as I came back to research only 12 years after. I love this paper because it took me a lot to publish it, not simply for producing results and writing the draft, but especially because one of the referees was strongly against its publication and I had to defend it really hard to convince the editor. The topic was really fascinating and actually very hot at those times: the question was about water dissociating or not at catalytic metal surfaces, and exploring the possibility of producing hydrogen. Many scientists were excited at the experimental and theoretical evidence assessing water dissociation. With my calculations I could show that both the dissociated and undissociated systems were possible, as for geometric properties the first was in line with LEED experiments, whereas for electronic properties the second was matching work function measurements. Subsequently, the scientific community had investigated further and found that a mixture of the two situations was the reality.

I currently use the Car-Parrinello method for performing ab initio molecular-dynamics simulations on superionic systems. This method is clever and elegant, and its advent in 1985 historically made possible to perform dynamics simulations using first principles, i.e. without prior knowledge of experimental parameters, only by knowing the number and types of atoms and their initial positions. I’d like to cite this 1991 Physical Review A paper by Pastore, Smargiassi and Buda that gives a nice overview of the method and of the reasons it works.