It turned out that the negative compressibility of sodium amidoborane crystals has to be a consequence of the elongation of the chemical bonds between nitrogen and hydrogen and boron and nitrogen, caused by the abrupt formation of new hydrogen bonds between adjacent molecules in the crystal. (sciencedaily.com)
«Our finding might open the door to uncharted territory in the area of negative compressibility, which potentially features a whole variety of bulk correlated metals,» said He. (sciencedaily.com)
The difference in the maximum value of the isothermal compressibility between the two isotopes shows the importance of nuclear quantum effects. (science.sciencemag.org)