ON THE POSSIBILITY OF HAVING DIFFERENT BRAVAIS LATTICES CONNECTED THERMODYNAMICALLY

`It is generally accepted that the simplest kinds of crystals exhibit 14 kinds of symmetry, the Bravais lattices described in texts treating crystals. Briefly, Bravais's idea was to regard two configurations as having the same symmetry provided they can be connected by a special kind of path, in the space of lattice vectors. However, with his assum ptions, he overlooked the possibility that some of the 14 can be joine d by such paths, which reduces the 14 to 11. To be explored is the que stion of whether paths found to connect the different Bravais lattices are thermodynamically possible, when pressure and temperature are sui tably controlled.