The Chem3D ActiveX/Plugin can be used to view many file formats. Here are some examples:

C3XML (Chem3D native file format) ChemDraw CDX file MDL MOL file |  | Sybyl MOL2 file PDB (Protein Data Bank) Macromolecular CIF

Here is a complete list of the file formats that can be loaded into the control:

File Format Name | File Extensions
Chem3D XML | .C3XML
Chem3D 8.0 | .C3D; .C3T
Chem3D 3.2 | .C3D
Alchemy | .ALC; .MOL
Cart Coords 1 | .CC1
Cart Coords 2 | .CC2
CCDB | .CCD; .DAT
ChemDraw | .CDX; .CHM
ChemDraw XML | .CDXML
Chemical Markup Language | .cml; .xml
Conn Table | .CT; .CON
Gamess Input | .INP
Gaussian Input | .GJC; .GJF
Gaussian Checkpoint | .FCHK; .FCH
Gaussian Cube | .CUB
Int Coords | .INT
ISIS Sketch | .SKC
ISIS Transportable Graphics | .TGF
MacroModel | .MCM; .DAT; .OUT
MDL MolFile | .MOL
mmCIF | .CIF
MSI ChemNote | .MSM
MOPAC Input | .MOP; .DAT; .MPC; .ZMT
MOPAC Graph | .GPT
Protein Data Bank | .PDB; .ENT
SDFile | .SDF
SMDFile | .SMD
SYBYL | .SML
SYBYL2 | .MOL2; .SM2; .ML2
SMILES | .SMI