A metal organic framework should not be soluble in any solvent. if your powder is soluble in any solvent, than it likely to be an organometallic complex or, otherwise, an oligomeric species that turns into monomer.

Furthermore, you can try with PXRD. From this analysis you can see if your material is crystalline or not.

But, you could have an amorphous MOF and therefore not a good diffractogram.

I would suggest you, then, to test the solubility first.

Hope it helps

Metal "complexe'ss" definition comes from A. Werner. Complexes are composed by metal to oxygen or nitrogen bonds (some times phosphorus), but never carbon. The metal complex is generally a separated molecule with one or more metals in it but without connection to neighbor molecules. On the other hand, Cotton I believe, defined organometallic (circa 1964) as molecules with metal-to-carbon bonds (vitamin B12 for example). Besides that, coordination compounds can be tailored to have intermolecular bridges so as to build cages, tunnels, spheres, wheel catenated and so on. These supramolecular arrays (or FRAMES, frameworks) are very stable (Keq) and exchange ligands very slowly (k). Therefore the difference,  is a matter of design and structure but nature had already made "Zeolites" long before we started designing frameworks.If you can't crystallize'em heat'em. 

"Networked molecular cages as crystalline sponges for fullerenes and other guests" "Yasuhide Inokuma, Tatsuhiko Arai, & Makoto Fujita" Nature Chemistry, 2, 780–783, (2010). doi:10.1038/nchem.742

thanks Alessandro Poma and Victor Calvo-Perez. I hope this will for me.

I guess you should look around for metallo-organic-frameworks MOF literature. There are so many of them, but all has something in common, network structure. Therefore you need to get XRD quality crystals. Or at least cell parameters from powder diffraction.

Single Crystal XRD is only technique which confirms whether it is MOF or not.

A metal is just a simple element but when we talk of MOF it means there is a framework of atoms between a metal and an organic compounds or organic Ligands

In metal complex, the molecules are separated from each other. Whereas,

MOF is a stable supramolecular chain (framework) of repeating units.

Metal complex is often synthesized using ligands having one bonding point (e.g. -O, -N etc.), while MOFs are synthesized using chelated ligands having more than one bonding point.

Single crystal X-ray diffraction is the most applicable and accessible tool to confirm your products.

Check this article wherein it is clearly written on second page which I have posted here for your reference just in case if you do not have access.

" Wikipedia defines MOF as “crystalline compound consisting of metal ions or clusters coordinated to often rigid organic molecules to form one-, two-, or three-dimensional structures that can be porous”. This definition seems to be very specific for crystallinity and dimensionality; the latter is restricted to only extended interactions through covalent or coordinate bonds and not to other nonbonding interactions. Also, porosity is only an additional feature and is not particular to the definition. In fact, it was Yaghi who first introduced the term MOF for the newly synthesized copper 4,4′-bipyridyl complex that exhibited extended metal-organic interactions.According to him, “the term coordination polymer is undoubtedly the most nebulous, as it simply signifies the extended connection of metal and ligand monomers through coordination bonds with no regard towards the final structure or morphology”. In the literature, MOFs are quite often associated with hydrogen storage properties or in general, porosity; if the material does not exhibit this property, they are perceived to be coordination polymers!

Coordination Polymers Versus Metal−Organic Frameworks! "

Kumar Biradha*† Arunachalam Ramanan*‡ Jagadese J. Vittal*§ Cryst. Growth Des. 2009, 9, 7, 2969-2970

https://doi.org/10.1021/cg801381p

Thanks a lot, sir

Single crystal XRD and ESI-MS can help to differentiate between these two compound.

To differentiate between a metal organic framework and a metal complex one should know the type of bonding.In metal organic frame work. there is bond between carbon and metal whereas in metal complex one atom is a donor having the pair of electrons for coordination to the central metal atom.

MOF is formed from organic linkers/ chelate and metal nodes whereas complex is formed from organic or inorganic ligands. the ligand may be unidentate, bidentate or polydentate.