Slavi Sevov

Research Interests

Chemistry of Main-Group Metals and Semimetals in Negative Oxidation States

The heavier members of Groups 14 and 15, both metals and semimetals, are known for their chemistry in various positive oxidation states. What we are interested in is how they behave when forced to accept electrons and become negatively charged, i.e. when in negative oxidation states. It turns out that such atoms tend to cluster together and form: nine-atom deltahedral clusters E₉^4- for Si, Ge, Sn, and Pb; seven-atom species E₇^3- for P, As, and Sb; etc. We have studied extensively the reactivity of Ge₉^4- towards various reagents and have found, to our and many other people’s surprise, that they can be readily functionalized with various groups and form [R-Ge₉-R]^2- and [Ge₉-R]^3- for R = alkyl, alkenyl, main-group and transition-metal organometallic fragments, etc. Furthermore, they can oligo- and poly-merize to form dimers trimers, tetramers, and infinite chains, for example [Ge₉-Ge₉]^6-, [Ge₉=Ge₉=Ge₉]^6-, and [-(Ge₉^2-)-], and they can be centered by transition-metal atoms. The bismuth fragments, on the other hand, can react with various organometallic compounds and form mixed main-group/transition-metal clusters such as [Bi₃Mo₂(CO)₆]^3-, [Bi₃Ni₄(CO)₆]^3-, [Bi₄Ni₄(CO)₆]^2-, [Bi₃Ni₆(CO)₉]^3-, and the Ni-centered [Ni@{Bi₆Ni₆(CO)₈}]^4-.

Hydrothermal Exploratory Synthesis of Hybrid Organic-Inorganic Materials with Framework Structures

We are interested in compounds with open-framework structures as well as compounds that contain large multiatomic molecular anions built of transition-metal, borate, and phosphate or phosphonate groups. We have synthesized the first such open-framework borophosphate, CoB₂P₃O₁₂(OH)•en where ethylenediamine (en) is the organic template, and the first borophosphate templated by a transition-metal complex, [Co(en)₃][B₂P₃O₁₁(OH)₂]. Also, we have synthesized the first large borophosphate polyoxometalate, [Mo^V₅Mo^VI₇O₃₀(BPO₄)₂(PO₄)₃(HPO₄)₃]^8- and its phenyl-functionalized version [Mo^V₅Mo^VI₇O₃₀(BPO₄)₂(Ph-PO₄)₆]^5-. Other systems of interest include extended frameworks made of transition-metal centers connected by organic linkers with two or more functional groups such as di-phosphonates, carboxylate-phosphonates, boronate-phosphonates, carboxylate-boronates, etc.

Selected Publications

• Perla, L. G.; Munoz-Castro, A. and Sevov, S. C. "Eclipsed- and Staggered-[Ge18Pd3{E'Pr-3}(6)](2-) (E = Si, Sn): Positional Isomerism in Deltahedral Zintl Clusters" 2017 Journal of the American Chemical Society, 139 (42), pp.15176-15181. DOI: 10.1021/jacs.7b08562.
• Perla, L. G. and Sevov, S. C. "A Stannyl-Decorated Zintl Ion [Ge18Pd3(Sn ' Pr-3)(6)](2-): Twinned Icosahedron with a Common Pd-3-Face Or 18-Vertex Hypho-Deltahedron with a Pd-3-Triangle Inside" 2016 Journal of the American Chemical Society, 138 (31), pp.9795-9798. DOI: 10.1021/jacs.6b06545.
• Li, F.; Munoz-Castro, A. and Sevov, S. C. "[(Me3Si)Si](3)EtGe9Pd(PPh3), a Pentafunctionalized Deltahedral Zintl Cluster: Synthesis, Structure, and Solution Dynamics" 2016 Angewandte Chemie-International Edition, 55 (30), pp.8630-8633. DOI: 10.1002/anie.201603374.
• Perla, L. G. and Sevov, S. C. "Cluster Fusion: Face-Fused Nine-Atom Deltahedral Clusters in [Sn14Ni(CO)](4-)" 2016 Angewandte Chemie-International Edition, 55 (23), pp.6721-6724. DOI: 10.1002/anie.201602837.
• Perla, L. G. and Sevov, S. C. "[Bi12Ni7(CO)(4)](4-): Aggregation of Intermetalloid Clusters by their Thermal Deligation and Oxidation" 2015 Inorganic Chemistry, 54 (17), pp.8401-8405. DOI: 10.1021/acs.inorgchem.5b01101.
• Li, F. and Sevov, S. C. "Coordination of Tri-Substituted Nona-Germanium Clusters to Cu(I) and Pd(0)" 2015 Inorganic Chemistry, 54 (16), pp.8121-8125. DOI: 10.1021/acs.inorgchem.5b01371.