The Effect of Temperature on the Atomic Distribution in Liquid Potassium

X-ray diffraction patterns of liquid potassium at temperatures of 70°C, 200°C, 295°C and 395°C have been obtained, using Mo Kα radiation. Three peaks appear in each pattern, and with increasing temperature, the peaks become somewhat less pronounced. The first, and most intense, peak appears at a scattering angle of 10° 36′ in the 70°C case, and it appears at 10° 16′ in the 395°C case. Fourier analysis applied to the above two cases gives the atomic distributions at these temperatures. In the 70°C distribution curve, the maximum of the first peak occurs at 4.64A, that of the second peak at 9.0A, and after this, the distribution rapidly becomes random. In the 395°C distribution curve, the maximum of the first peak occurs at 4.8A, that of the second at 9.2A, and beyond this the distribution becomes random more rapidly than in the 70°C case.