Molecule structure of Nickel iron sulfide (CAS NO.59978-65-3):

IUPAC Name: Iron(3+); nickel(2+); tetrasulfide 
Molecular Weight: 418.8786 g/mol
Molecular Formula: FeNi₄S₄⁺³ 
Enthalpy of Vaporization: 18.67 kJ/mol
Vapour Pressure: 12600 mmHg at 25 °C
H-Bond Acceptor: 4
Exact Mass: 417.560059
MonoIsotopic Mass: 415.564616
Heavy Atom Count: 9
Formal Charge: 3
Canonical SMILES: [S-2].[S-2].[S-2].[S-2].[Fe+3].[Ni+2].[Ni+2].[Ni+2].[Ni+2]
InChI: InChI=1S/Fe.4Ni.4S/q+3;4*+2;4*-2
InChIKey of Nickel iron sulfide (CAS NO.59978-65-3): FRWHRIRADSHXLL-UHFFFAOYSA-N

NTP 10th Report on Carcinogens. Nickel and its compounds are on the Community Right-To-Know List.

Confirmed human carcinogen with experimental carcinogenic and neoplastigenic data. When heated to decomposition it emits toxic fumes of SO_x. See also NICKEL COMPOUNDS, SULFIDES, and IRON COMPOUNDS.

OSHA PEL: TWA 1 mg(Ni)/m³
ACGIH TLV: TWA 1 mg(Ni)/m³; Not Classifiable as a Human Carcinogen
NIOSH REL: (Inorganic Nickel) TWA 0.015 mg(Ni)/m³

 Nickel iron sulfide (CAS NO.59978-65-3) is also named as CCRIS 7589 ; Iron nickel sulfide ; Nickel ferrosulfide ; Nickel-iron sulfide matte ; Nickel ferrosulfide .