mercuric amidochloride is an inorganic compound with the formula hgnhcl. it consists of a zig-zag 1-dimensional polymer (hgnh) with chloride counterions. it arises from the reaction of ammonia and mercuric chloride. addition of base converts it into "millon's base", which has the formula [hgn]oh·(ho). a variety of related amido and nitrido materials with chloride, bromide, and hydroxide are known.