The spheres are located at each vertex of the cube, and one in the center or body.[br]The spheres in the vertices contribute with (1/8).[br]The sphere in the center of the cell is complete.[br]There are 8 vertices, and with the sphere in the center of the cell, there are 2 complete spheres per unit cell.[br][br][br]Versión en español:[br]https://www.geogebra.org/m/p7w6g9we[br][br][br]Other structures:[br][br]Crystal structure - simple cubic:[br][url=https://www.geogebra.org/m/rxvmc3uj]https://www.geogebra.org/m/rxvmc3uj[/url][br][br]Crystal structure - face centered cubic:[br][url=https://www.geogebra.org/m/jcba9wnb]https://www.geogebra.org/m/jcba9wnb[/url][br][br]