Electron spin transient nutation

To investigate multispin systems, the so-called electron spin transient nutation (ESTN) spectroscopy is recently elaborated. This is a version of pulsed ESR. Nutation is the precessional motion of spin. The method and its applications are detailed in the paper of Itoh et al. (1997). Chapters 1 and 8 describes that the determination of spin multiplicity becomes a very important problem in organic chemistry of ion-radicals. 

In order to identify the spin multiplicity of the tris(carbene), field-swept two-dimensional electron spin transient nutation (2D-ESTN) spectroscopy was used. This technique is based on pulsed fourier transform (FT) EPR spectroscopic methods and is capable of elaborating straightforward information on electronic and environmental strucmres of high-spin species even in amorphous materials, information that conventional CW EPR cannot provide. The nutation spectra unequivocally demonstrated that the observed fine structure spectrum is due to a septet spin state. 

It is of interest to describe spin systems that are completely different from nitrox-ide-labeled dendrimers, but that also bear in their organic structure a high-spin multiplicity (with S > V) High-spin polycarbenes with ji-conjugation, which are the first and second generations of the spin-mediated dendrimers based on pheny-lacetylenes, were studied by a two-dimensional electron-spin transient nutation (2D-ESTN) method based on pulsed-ESR to determine the spin mulliphcity. The contour plots of the 2D-ESTN spectra of the dendrimer at 3.5 K allowed to identify the nutation frequencies, which were attributed to 4, 4> 4, 3>, 4, 3> <-> 4, 2>, 4, 2> 4, 1>, and 4, 1> 4, 0>. The ESR allowed the detec-... 

Wilier M, Schweiger A. 1997. Determination of g values by a new electron spin transient nutation experiment the gj value of titanimn-doped sapphire. Chem Phys Lett 264 1-8. 

Astashkin AV, Schweiger A. 1990. Electron-spin transient nutation a new approach to simplify the interpretation of ESR spectra. Chem Phys Lett 174 595-602. 

Takui, T., Sato, K., Shiomi, D., Itoh, K., Kaneko, T, Tsuchida, E., and Nishide, H., FT pulsed ESR/electron spin transient nutation spectroscopy in the study of molecular based magnetism applications to high-spin polymers and ferromagnetic materials. Mol. Cryst. Liq. Cryst., 271, 191, 1995. 

These so-called transient nutations are observed if resonance between an electron spin transition and a coherent radiation field is suddenly achieved. The phenomenon can be understood when viewing the motion of the magnetization vector, M, in a... 

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