Henry Rzepa's Blog

I thought I was done with exploring anomeric effects in small sulfur rings. However, I then realised that all the systems that I had described had an odd number of atoms and that I had not looked at any even numbered rings. Thus hexasulfur is a smaller (known) ring version of S₈, the latter by far the best known allotrope of this element of course.

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Last year I reminisced on the occasion of the 40th Anniversary of the Macintosh computer.[cite]10.59350/f11dr-93t29[/cite] Four decades of advances in technology now mean I can do a fair amount of computational quantum modelling on a recent Mac (one from 2022 with M1 processor), and since then they have only got even (~2 or 3 times) faster with the M4 processor. Many of the recent calculations done for these blogs have included at least one or two that were done on the Mac. So I was intrigued to find that a real working version of the original Mac is about to be released for sale, but with a twist. Its called the “Pico-mac-nano” and from its name it is truly diminutive, being only 6.2 cm high – half the height of a can of cola – and with a 2″ LCD display. It comes with a connector for a keyboard and mouse, although currently it has no sound.

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