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Solid-state (super 93) Nb NMR spectroscopy and (super 13)C NMR experiments are show to be very sensitive and rapid probe of molecular structure and purity in half-sandwich metallocenes. Relationships between tensor orientations the principal components and molecular structures are determined by theoretically calculating CS and electric field gradient (EFG) tensors.

The first solid-state (super 39)K NMR spectra of organometallic complexes cyclopentadienyl potassium (CpK) and pentamethylcyclopentadienyl potassium (Cp*K) is presented. A high S/N (super 39)K spectrum of broad central transition of Cp*K with a breadth of ca. 200 kHz is acquired with the help of piecewise quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) NMR techniques.

The quadrupolar Carr-Purcell Meiboom-Gill pulse sequence that is used in the rapid acquisition of solid-state NMR spectra of half-integer quadrupolar nuclei is studied. Its observed that chemical shielding tensor parameters can be determined from the rapidly acquired spectra more accurately than with corresponding CP/MAS spectra.

The use of signal enhancement schemes such as bis(cyclopentadienyl)diclorozirconium(IV) DFS/QCPMG, QCPMG for the acquisition of (super 91) ZR NMR spectra permits the study of an organometallic Cp2ZrCl2 as well as inorganic material with a large quadrupolar interaction, a ceramic zirconium oxide NMR rotor.

A variety of sodium metallocenes were studied by (super 23)Na (I = 3/2) and (super 13)C solid-state numeric magnetic resonance (NMR). A variable-temperature (super 23)Na NMR experiments showed that the magnitude of C(sub Q)((super 23)Na) grows with increasing temperature in the linear metallocenes.

Solid-state double-resonance and triple-resonance (super 13)C, (super 11)B, and (super 1)H NMR experiments are used to investigate two main group metallocence complexes. Boron-11 nuclear quadrupole coupling constants reflect the higher spherical symmetry of [Cp*2B](super +1) compared to Cp*(sub 2)BMe, with C(sub Q)(super 11)B = 1.14 MHz in the former and C(sub Q)(super 11)B = 4.52 MHz in the latter.

The local structures and oxygen/fluorine ordering of Cdpy4NbOF5 (py = C5H5N) and [pyH](sub 2)[Cdpy4(NbOF5)(sub 2)] are examined with (super 93)Nb, (super 19)F, and (super 113)Cd solid state NMR spectroscopy. A process to extract the nuclear quadrupole coupling constant, the asymmetry parameter and isotropic shift in the presence of big chemical shift anisotropy is presented.

A variety of NMR interactions were characterized by solid-state NMR spectroscopy in potassium heptafluoroniobate, K2NbF7, which contains fluorine atoms arranged about a central niobium atom in heptacoordinate , capped trigonal prism arrangement. The variable-temperature (super 19)F MAS NMR demonstrate that intramolecular fluorine motion becomes significant above -100 degreeC resulting in a reduction in the fluorine second moments and the (super 93)Nb, (super 19)F dipolar coupling.

Details of NMR studies on cobaloximes containing 15N-labeled pyridine and aniline are presented.

Examples of two extremes of(super 27)Al chemical shielding anisotropy, namely, small values in pseudo-octahedral complexes and large values in diatomic and linear triatomic molecules are investigated. Small spans were obtained from six-coordinate compounds Al(acac)3, Al(THMD)3 and Al(trop)3 from solid state Al NMR spectra while large spans in AlNC and AlCl were obtained from Al nuclear spin-rotation constants from microwave spectra. Theoretical Al chemical shielding tensors obtained from Hartree-Fock and density functional theory methods are also discussed.