Before you read this, I suggest you read post 16.18. I have written this post not because I know a lot about the subject but because I find some aspects of it interesting. “The naming of cats is a difficult matter.” T.S. Elliot (American/British poet, 1888-1965) Old Possum’s Book of Practical Cats. So let’s see… Continue reading 23.5 Biological classification – taxonomy

If you want to understand the background to this post, I suggest you read posts 22.12, 22.14, 22.15, 22.20, 22.21, 22.23, 22.24, 23.1 and 23.3 (route 1). But, for a less mathematical introduction, you can read posts 18.10, 18.16, 22.21 (but not the last paragraph) and 23.2 (route 2). Most of the statements that appear… Continue reading 23.4 X-ray crystallography and molecular structure

Before you read this, I suggest you read posts 22.14 and 22.21. In post 22.21, we saw that an ideal crystal is an arrangement of atoms (that may be bonded together in molecules) or ions in a regularly repeating three-dimensional pattern. And, in post 22.14, we saw that the x-ray diffracted by an object could… Continue reading 23.3 X-ray diffraction by a crystal