Single molecule scattering

This total intensity is made up of single molecule scattering... 

P. A. Derosa, and J. M. Seminario, Electron transport through single molecules scattering treatment using density functional and green function theories, J. Phys. Chem. B 105, 471 —481 (2001). 

There has been a tendency in the OKE literature to ascribe the former feature to DID effects, based in part on a similarity to a prediction for the lineshape of DID scattering in atomic fluids (66). Similarly, the latter feature is often attributed to single-molecule scattering. It is doubtful that any such... 

Mesogens combining molecular features of both rod and disc appear to favor the formation of biaxial nematic phases [107-109]. However, a subsequent NMR study of 2,3,4-tri-n-hexyloxycinnamic acid showed that any biaxiality of the nematic phase is very small, less than 0.1 [110]. The influence of molecular biaxiality on intramolecular X-ray scattering has been assessed [111], and the calculations show that inclusion of biaxial ordering makes a very small contribution to the single molecule scattering. 

Figure 2. Calculated single molecule scattering from PAA difference molecules with (a) a sharp orientational distribution and (b) a Mai-er-Saupe distribution with 2=0.429.

It has been shown [8] that the single molecule scattering depends on the order parameters and a series of structure factors which act as coefficients to the terms in the series... 

The single molecule scattering has its maximum at Q = 0 where So(Q) is fixed by the number of substituted atoms in the molecule so the scaling parameter, K, is easily determined. This means that all of the order parameters may be determined individually. However, there are a number of experimental factors that can influence the accuracy of the order parameters determined by the single molecule scattering method. 

Nie S and Emory S R 1997 Probing single molecules and single nanoparticles by surface-enhanced Raman scattering Science 275 1102-6... 

Kneipp K, Wang Y, Kneipp H, Itzkan I, Dasari R R and Feld M S 1996 Approach to single molecule detection using surface-enhanced Raman scattering ICORS 98 XVth Int. Conf on Raman Spectroscopy ed S A Asher and P B Stein (New York Wley) pp 636-7... 

In a dilute gas with molecules significantly smaller than the wavelength of light, the individual molecules act as point scatterers. For a gas consisting of N molecules in a volume of V m, the total scattering is A/V times the scattering from a single molecule. 

Kneipp, K., Wang, Y., Kneipp, H., Perelman, L. T., Itzkan, I., Dasari, R. R. and Eeld, M. S. (1997) Single molecule detection using surface-enhanced Raman scattering (SERS). Phys. Rev. Lett., 78, 1667-1670. 

Xu, H., Aizpurua, J., KaD, M. and Apell, P. (2000) Electromagnetic contributions to single-molecule sensitivity in surface-enhanced Raman scattering. Phys. Rev. E, 62, 4318-4324. 

Kneipp K., Kneipp H., Deinum G., Itzkan I., Dasari R.R., Feld M. S., Single-molecule detection of a cyanine dye in silver colloidal solution using near-infrared surface-enhanced Raman scattering, Appl. Spectrosc. 1998 52 175-178. 

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