( Rhenium ( ( is ( ( the ( only metal ) ) ( ( known ( to bond ) ) ( with ( ( ( seven fluorides ) , ) ( which ( is ( ( the record ) ( for ( number ( of ( ( charged ligands ) ( for ( a ( charge-neutral ( metal compound ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Rhenium)) (VP (VBZ is) (NP (NP (DT the) (JJ only) (NN metal)) (VP (VBN known) (PP (TO to) (NP (NN bond))) (PP (IN with) (NP (NP (CD seven) (NNS fluorides)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (NP (NP (DT the) (NN record)) (PP (IN for) (NP (NP (NN number)) (PP (IN of) (NP (NP (JJ charged) (NNS ligands)) (PP (IN for) (NP (DT a) (JJ charge-neutral) (NN metal) (NN compound)))))))))))))))) (. .)))
Rhenium is the only metal known to bond with seven fluorides, which is the record for number of charged ligands for a charge-neutral metal compound.
(ROOT (S (NP (JJ Iconic) (NNS compounds)) (VP (VBP have) (NP (DT a) (JJ net) (JJ neutral) (NN charge))) (. .)))