Chromium is somewhat like a simple antiferromagnet, but also has an incommensurate spin density wave modulation on top of the simple up-down spin alternation.[8] Manganese (in the α-Mn form) has 29 atoms unit cell, leading to a complex, but commensurate antiferromagnetic arrangement at low temperatures (magnetic space group P42'm').[9][10] Unlike most elements, which are magnetic due to electrons, the magnetic ordering of copper and silver is dominated by the much weaker nuclear magnetic moment, (compare Bohr magneton and nuclear magneton) leading to transition temperatures near absolute zero.[11][12]