Research output: Contribution to journal › Article › peer-review
A combined XRD and theoretical study for two adducts, [Pt(acac)2]·2(1,3,5-FIB) and [Pd(acac)2]·1,3,5-FIB (Hacac = acetylacetone; 1,3,5-FIB = 1,3,5-triiiodotrifluorobenzene), reveals that differences in the type formed halogen bond (XB) depend on the identity of the metal center. Only [Pt(acac)2] forms rare two-center metal-involving XB Ar-I⋯[dz2PtII] (where the positively charged PtII center acts as a nucleophile toward an iodine σ-hole), while three-center bifurcated XB I⋯η2(O,O) was detected in both adducts. The observed linkage Ar-I⋯[dz2PtII] provides an experimental argument favoring the previously established (by a kinetic study) XB-formation step upon oxidative addition of I2 to [Pt(acac)2]. The variable temperature XRD study of [Pt(acac)2]·2(1,3,5-FIB) (100-300 K; five XRD experiments) demonstrates that the I⋯Pt and I⋯O contacts weaken simultaneously on heating that allows the consideration of the Pt1-O2 bond as an integrated XB acceptor. Appropriate DFT calculations (M06/DZP-DKH level of theory) performed by single-point "quasi-solid state" calculations with topological analysis of the electron density distribution within the framework of the Bader theory (QTAIM method), confirmed the existence of the two-center metal-involving XB I⋯Pt in the structure of [Pt(acac)2]·2(1,3,5-FIB) and three-center I⋯η2(O,O) bifurcated XBs for both adducts. All these interactions exhibit a non-covalent nature with estimated energies in the range of 2.1-4.3 kcal mol-1.
Original language | English |
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Pages (from-to) | 554-563 |
Number of pages | 10 |
Journal | CrystEngComm |
Volume | 22 |
Issue number | 3 |
DOIs | |
State | Published - 21 Jan 2020 |
ID: 51282529