[Benzene]

just a general question about Palladium. it seems like there are always 4 lone pairs around the metal center. when palladium is in its (0) oxidation state, its valence its filled, why do these bonds form?
example: tetrakis
http://en.wikipedia.org/wiki/Tetrakis(triphenylphosphine)palladium(0)

[kriggy]

4 pairs? Doesnt Palladium has d10 configuration?
If you are talking about the bonds with phosphorus, its coordination compound. The bond is made by phosphorus donating its lone electron pair to empty orbitals of Palladium.

[Benzene]

4 pairs? Doesnt Palladium has d10 configuration?
If you are talking about the bonds with phosphorus, its coordination compound. The bond is made by phosphorus donating its lone electron pair to empty orbitals of Palladium.

Yes I am talking about the bonds with phosphorus. Palladium does have a d10 configuration. So all the 4d orbitals are full. what empty orbitals are available? 5s and 5p?

[kriggy]

Yes, 5s 5p orbirals are empty and ready to accept electrons from phosphorus. Note that phosphorus itself has empty d orbitals so there is donation of electrons from palladium to phosphorus.