Stark-effect spectroscopy

Palacios, M.A., Frese, R.N., Gradinaru, C.G., Premvardhan, L., Horton, P., Ruban, A.V., van Grondelle, R., and van Amerongen, H. 2003. Stark effect spectroscopy of the different oligomerisation states of lightharvesting complex II. Biochim. Biophys. Acta 1605 83-95. 

Pierce DW, Boxer SG (1995) Stark effect spectroscopy of tryptophan. Biophys J 68 1583-1591... 

The principle behind this investigation is electrochromism or Stark-effect spectroscopy. The electronic transition energy of the adsorbed chromophore is perturbed by the electric field at the electric double layer. This is due to interactions of the molecular dipole moment, in the ground and excited states, with the interfacial electric field induced by the applied potential. The change in transition frequency Av, is related to the change in the interfacial electric field, AE, according to the following ... 

The effect of an electrical field on the absorption/emission of spectra of a probe such as fluorescein or a coumarin derivative. It is derived from the interaction of the induced dipole(s) in the probe interacting with the charged group. See Sitkoff, D., Lockhart, D.J., Sharp, K.A., and Honig, B., Calculation of electrostatic effects at the amino terminal of an helix, Biophys. J. 67,2251-2260,1994 Pierce, D.W. and Boxer, S.A., Stark effect spectroscopy of tryptophan, B/opfiyx. J. 68,1583-1591,1995 Klymchenko, A.S., Avilov, S.V., and Demchenko, A.P., Resolution of Cys and Lys labeling of a-crystalUn with site-sensitive fluorescent 3-hydroxyflavone dye. Anal. Biochem. 329, 43-57, 2004. 

Boxer introduced using electrooptical (Stark effect) spectroscopy for determining d 2 of metal-centered IV complexes and other ET problems (calling them effective ET distances).59 63 These methods have also been applied by the groups of Hupp64 68 and of Sutin.69,70 We have not had access to the necessary equipment for this experiment, and have used other methods of estimating di2. 

D.J. Lockhart and S.G. Boxer, Stark effect spectroscopy of Rhodobacter sphaeroides and Rhodopseudomonas viridis reaction centers, Proc. Natl. Acad. Sci. USA 85 107 (1988). 

STARK EFFECT SPECTROSCOPY OF THE Rb. SPHAEROIDES HETERODIMER MUTANT... 

As first shown by Boxer et al. electroabsorption (or Stark effect) spectroscopy provides an experimental method to determine the extent of delocalization in mixed-valence complexes. Unfortunately, the technique is experimentally very difficult and this has limited its application. Nevertheless, Stark effect measurements of parallel and orthogonal intervalence transitions in... 

Chattopadhyay, A., Boxer, S.G. Vibrational Stark-effect spectroscopy. J. Am. Chem. Soc. 

Not only can electronic wavefiinctions tell us about the average values of all the physical properties for any particular state (i.e. above), but they also allow us to tell us how a specific perturbation (e.g. an electric field in the Stark effect, a magnetic field in the Zeeman effect and light s electromagnetic fields in spectroscopy) can alter the specific state of interest. For example, the perturbation arising from the electric field of a photon interacting with the electrons in a molecule is given within die so-called electric dipole approximation [12] by ... 

A MBER spectrometer is shown schematically in figure C1.3.1. The teclmique relies on using two inhomogeneous electric fields, the A and B fields, to focus the beam. Since the Stark effect is different for different rotational states, the A and B fields can be set up so that a particular rotational state (with a positive Stark effect) is focused onto the detector. In MBER spectroscopy, the molecular beam is irradiated with microwave or radiofrequency radiation in the... 

Wild U P, Guttler F, Pirotta M and Renn A 1992 Single molecule spectroscopy stark effect of pentacene in p-terphenyl Chem. Phys. Lett. 193 451-5... 

Microwave spectroscopy (Stark effect). d, the probable approximate angle between the direction of fj, and the symmetry (or near symmetry) axis of the ring through atom N-1, in the molecular plane, has the value 69°. 

The experimental values for the dipole moment of furan vary somewhat according to the method used and to the conditions employed it is now agreed, however, that the use of the Stark effect in microwave spectroscopy gives the most accurate result (0.661 D) for the gas phase (51JCP(19)1609). In the past, values up to 0.72 have been used, especially for... 

The electric dipole moment components of the dipole of the THP-H20 complex have been determined using Stark-effect FT microwave spectroscopy. Only a- and c-type spectra were observed, which is consistent with computational studies <1998CPL(297)543>. 

Whilst the most important examples of Zeeman and Stark effects in 1A states are found in molecular beam studies, they can also be important in conventional absorption microwave rotational spectroscopy, as we describe in chapter 10. The use of the Stark effect to determine molecular dipole moments is a very important example. 

In this section we have described in considerable detail just one aspect of the spectroscopy of OH, namely, the measurement of zl-doubling frequencies and their nuclear hyperfine structure. This has led us to develop the theory of the fine and hyperfine levels in zero field as well as a brief discussion of the Stark effect. We should note at this point, however, that OH was the first transient gas phase free radical to be studied by pure microwave spectroscopy [121], We will describe these experiments in chapter 10. We note also that magnetic resonance investigations using microwave or far-infrared laser frequencies have also provided much of the most important and accurate information these studies are described in chapter 9, where we are also able to compare OH with the equally important radical, CH, a species which, until very recently, had not been detected and studied by either electric resonance techniques or pure microwave spectroscopy. 

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