Closing Remarks by Stephen R. Elliott

I was very pleased, at first, to see my friend Ladislav Cervinka on Monday morning, before the start of the conference, because I’d not seen him for a long time. However, immediately after our initial greeting, his next words were: “would you like to give the closing remarks of the conference?” Although this is a considerable honour, I must say my heart sank immediately, for 2 reasons: first, the great responsibility of adequately summarizing the very many contributions presented at the meeting, and second, rather shamefully, the dawning realization that acceptance of his kind offer would severely curtail my sight-seeing possibilities in this beautiful city because, necessarily, I would have to attend every session, listen to every talk and visit every poster, rather than, as I’m afraid, is my usual habit at conferences, and maybe yours too, of just attending those sessions of particular interest and spending the rest of the time in tourism. However, I couldn’t refuse Ladya and his request, and as a consequence of this enforced attendance, I found it a very educational experience! I would therefore recommend the following procedure to the Chairman of the next conference, NCM11, that, in order to increase attendance at all sessions, every participant be separately, and secretly, invited to give the closing remarks. In this way, everyone will be encouraged to attend all talks and posters, and the Chairman can then choose 1 person randomly at the last minute actually to give the remarks. I guarantee this will be most effective – if not too popular!

Ladya asked me to talk about the highlights of the conference. For me the highlight – that is the cultural highlight – was the Ravel piece played as an encore by the violin soloist at the concert in the Klementinum on Tuesday. I didn’t know this piece before, nor in fact some of the others played in the concert, and it was a particular delight. That, and the French horn playing by the leader of a jazz band playing on the Charles Bridge, encountered on the walk back. The French horn is a fiendishly difficult instrument to play well – or at all – yet this chap produced the most extraordinary sounds from it, seemingly effortlessly. Incredible.

However, obviously, I should concentrate on the scientific aspects of the conference. I think that this conference ahs been extremely successful, offering a showcase of much of what is newest and most interesting in this field. There have been some truly excellent and inspiring talks and posters.

First, perhaps some statistics to complement those on attendance given by Ladya, at the start. There were about 70 talks – invited and contributed – and about the same number of posters actually presented. It might be of interest to break down these contributions into the types of materials studied and techniques used, so I’ve done a quick count from the Abstracts, and come up with the following. (Subject to quite large error bars as insisted upon by the Journal of Non-Cryst. Solids!)

There was just 1 paper on a-Si and 1 other on a-C. Organic materials fared slightly better with 5 presentations, and halide-containing materials were even more popular with 8 papers. There was a healthy number of 17 papers on amorphous metals. Chalcogenide materials were really quite popular with 33 papers, but as they say at the Oscar’s ceremony, the winner of the category for most popular class of material at NCM10 was:- oxide glasses with 72 papers in total. Let’s hear it for oxides! This result is perhaps not too surprising bearing in mind the history of the subject. I was personally very gratified, however, to find so many papers on chalcogenides because I work on these materials. The reason for this popularity may be due to 2 factors, one technological and one demographic. We’ve heard during this conference that chalcogenides have very interesting technological applications, notably as the basis of phase-change data-recording media, most recently in Blu-Ray rewriteable DVDs using optical recording, and, I heard, informally here, that Samsung have just announced the launch early next year, of a PC-RAM, an electronically programmable random-access memory device based on PC chalcogenide materials.

The other reason might be one of demography and geography. Semiconducting chalcogenide glasses were first discovered by Kolomiets at the Ioffe Institute, in what was then Leningrad in the USSR, in the 1960s. There is still a lot of work being carried out on chalcogenides in what used to be called the Eastern-bloc countries, and we are fortunate that some of these colleagues from these countries were able to come to this conference and present their work. However, work on chalcogenides is now global, with much work going on in the U.S., U.K, Korea and, of course, Japan, as we have heard and seen here.

A breakdown of techniques used in the presented work is also illuminating. Most papers were experimental in nature, although an appreciable number of simulation papers were also presented, including 12 or so on Molecular Dynamics (MD). Of these, a sizeable fraction used various variants of ab initio MD, which I think is a very welcome development, promoted perhaps by 2 things: the wider availability of much more powerful computers (or clusters thereof), and of the increasing general public availability of such ab initio codes, meaning that researchers other than just the developers of the codes can do such simulations. Of the experimental structural techniques used in the work presented here, NMR and X-ray absorption spectroscopy were about equally popular, with about a dozen papers each, but the winner of the category for most popular technique at NCM10 was diffraction. So, if you’re doing diffraction experiments on oxide glasses, you should feel rather smug as being in the majority!

I always think it is a bit invidious to single out in Closing Remarks one or two individual papers presented at a meeting as being the most significant or important. Such choice often simply reflects the interests, or worse, prejudices, of the reviewer, and is unfair on all the other excellent papers not singled out in this way. So I shall resist this temptation.

Instead, I will close with a few concluding remarks. What has struck me forcibly here has been the very rapid technique development, especially in NMR and scattering methods, which now allow experiments to be performed which were unthinkable a few years ago. In the case of scattering methods, for example, levitation techniques now allow measurements to be made on high-temperature melts of refractory materials. As someone long interested in medium-range order, it is very gratifying also to find that it is now proving possible to determine the MRO in some cases, say concerning polyhedral connectivity information, e.g. by NMR.

What would it have been nice to have had more of here? Speaking personally, I think it would have been good to have a bit more proper theory – rather than simulation – although it can be difficult to get this over clearly. One should always remember Steven Hawking’s aphorism concerning the writing of his book “A Brief History of Time” – every extra equation halves the readership. However, I know that I am as guilty as anyone here in flooding the screen with equations in my presentations. More dynamics would have been nice too, and it was a shame that the Pisa conference on atomic dynamics of glasses and liquids overlapped with this meeting. It would also have been interesting to have had more work on polymers and organic systems. Perhaps this topic might be a focus for future NCM meetings.

Finally, I will end with an appreciation. Conferences are not organised, and run like clockwork as this has, without a huge amount of work behind the scenes. So, on behalf of you all, I would like to make the following thanks. First, to Jaroslav for ensuring that the computer and projector worked seamlessly. I must say that this is one of the very few conferences I have been to where there have been no computer crashes or inordinate pauses between talks. Second, we should thank Lenka for rushing around the auditorium with the microphone to enable the questioners to be heard – although I have to say that, whilst he was here, she ended up going mostly to Linn Hobbs who seemed to ask most of the questions. Thanks to you both. Thanks are also due to the helpers manning the registration desk and to the hotel staff for sustaining us during our stay here.

However, our principal debt of gratitude should be reserved for Ladislav Cervinka. Not only has he organised the meeting so efficiently, but at very short notice he has had to take over the editing of the proceedings as well. So, Ladya, from all of us, may I say thank you – dekuji!