Well, I have some time to waste, and since my name was just mentioned... I think a black box is a wonderful idea for cases where the space of possible solutions is very limited. At the same conference that the UK group presented, Wolfram Meyer-Klaucke gave a very nice talk on a black-box system for determining protein structure around an active site. The talk was opposite the UK group's, so unfortunately no one saw both. In any case, that's a perfect situation for automation: there are a very limited number of ligands that could be present, and their structures are very well understood. It's much more than fingerprinting, since the combination of ligands might never have seen before. Their system even allows for the ligands to be at slightly unusual distances. But it only works because the biochemistry is already pretty well understood and quite limited. Although a very different system, I suspect the UK automation of supported metal catalysts has similarly limited scope; neither system would probably work very well when fed data meant for the other! I think there's sometimes a wish for a system that acts like a Star Trek tricorder: stick any spectrum in, and the computer can say "it appears to be an oxide with coordination number 6." In my opinion, that kind of system will never be developed, because there just isn't that much information sitting in the EXAFS. (Some of you new to EXAFS may be puzzled by that--it doesn't sound like very much information at all. But if you're going to allow me the space of all possible structures along with less-than-perfect data, it's hard to distinguish disorder from coordination number changes, for example, and it's in turn hard to distinguish true disorder from splitting below the resolution of the data.) In other words, current experts in EXAFS analysis don't act as black boxes to the outside world. If <pick-your-favorite-expert> were brought a spectrum and asked "OK, tell me the structure," the expert would immediately start asking questions to gain additional information (or would say "no," and walk off in a huff). If experts don't act as black boxes, then neither can a computer. OK, with my two cents added to Bruce, that now makes four... --Scott Calvin Sarah Lawrence College
Ah! The "black box" discussion. That's a fun way to waste lots of time. ;-)
The physics has its complicated parts, but I suspect that we have a sufficient understanding of the problems. There are many applications where a black box is reasonable to consider and probably would even work pretty well. At the recent XAFS conference, the group from Manchester, UK presented a high-throughput scheme that involves automate processing of larfge quantities of data. They seem to get good results with minimal human intervention. And Harald Funke gave a really neat talk about Feff-based wavelets that could be a very useful approach to a first-shell black-box.
There will always be a large part of exafs analysis that falls well outside the scope the black box. The sorts of crazy fits published by some of the frequent contributors to this list (I am thinking specifically of Scott Calvin and Shelly Kelly) will always defy automation.
Well, that was my US$0.02 worth... B