CALCIUM ION non-polymer HETAI Ca 2 1999-07-08 2011-06-04 N REL 40.078 CA N N RCSB CA CA 2 0 N N N 0.000 0.000 0.000 0.000 0.000 0.000 CA CA 1 [Ca+2] [Ca++] [Ca++] [Ca+2] [Ca+2] InChI=1S/Ca/q+2 BHPQYMZQTOCNFJ-UHFFFAOYSA-N calcium calcium(+2) cation RCSB RCSB