At first, we must take into account that in crystallography, vacancies account for the absence of an atom or molecule from a point that it would normally occupy in a crystal. In such a way, it has been widely studied that even crystalline solids have imperfections specially referred to vacancies created due to an eventual mechanical deformation of the crystal, rapid cooling from high temperature, or the impact of radiation on the crystal. Thus, it is false that one could produce a perfect crystalline solid that does not contain any vacancies.
<span>All crystalline solids contain vacancies. In fact, vacancies is one of the properties of a crystalline solids, for their presences is what creates their random (entropic) design. Furthermore, it is near impossible to create any solid matter that does not contain vacancies/defects. Vacancies can be created by the absence of an atom during matter creation; thermal vibrations can create such a defect as well.</span>
ad then 
, where 
is the sea level weight, 
the sea level accel., 
the accel. above while 
the weight above.<em />