Nuclear spin-lattice relaxation in trans-polyacetylene (CH)x. A confined soliton model including nuclear spin flip diffusion

نویسندگان

  • P. K. Kahol
  • M. Mehring
  • X. Wu
چکیده

2014 A « confined soliton model » in which the solitons move over a small part of the chain is developed. The on-chain nuclei are relaxed directly by contact hyperfine interactions whilst the remainder nuclei relax via nuclear spin flip diffusion. It is found that the proton spin-lattice relaxation data can be rationalized in terms of the fast and confined one-dimensional hopping motion of the soliton whilst that for enriched 13C one requires in addition a much more dominating mechanism that of nuclear spin flip diffusion. J. Physique 46 (1985) 1683-1691 OCTO.BRE 1985, Classification Physics Abstracts 76.60E

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Nuclear spin relaxation in glassy ionic conductors

The nuclear spin relaxation behaviour in disordered ionically conducting materials is ascribed to a mechanism based on diffusion-controlled relaxation. In this targetdiffusion model, relaxation is assumed to occur at interstitialcy sites, triggered by the arrival of diffusing ions. The dependence of the spin-lattice relaxation rate on the temperature, Larmor frequency and ionic concentration ca...

متن کامل

Spin Diffusion gd Orientation Dependence of Deuterium Tl in Solids

The study of spin diffusion in solids has been of recent interest. Spin diffusion occurs by flip-flop cross-relaxation due to the S$Sj_ + S!Sj, term of the dipolar couplings among the spins (I). When a large inhomogeneous interaction also exists for the S spin system, then the flip-flop transition may not conserve energy, i.e., the resonances of the coupled spins do not overlap and are separate...

متن کامل

Proton Dipolar Spin–Lattice Relaxation in Nano-channels of Natrolite

The 1H nuclear magnetic resonance (NMR) spectra and the dipolar spin-lattice relaxation time T1D for 1H in the natural natrolite (Na2Al2Si3O10·2H2O) have been measured in the temperature range of 190-390 K. From the temperature transformations of 1H NMR spectra, it follows that at T > 300 K, the diffusion of water molecules along the nano-channels is observed. From experimental T1D data, it fol...

متن کامل

Insight into lithium transport in lithium nitridometallate battery materials from muon spin relaxation.

Muon spin relaxation and powder neutron diffraction have been combined to study three lithium cobalt nitride battery materials. Neutron diffraction shows that these retain the P6/mmm space group of Li(3)N with Co located only on Li(1) sites. The lattice parameters vary smoothly with the degree of metal substitution, such that the [Li(2)N] layers expand while the layer separation contracts, as o...

متن کامل

Distinction between the Preneoplastic and Neoplastic State of Murine Mammary Glands by spin-echo NMR

We have, using spin-echo nuclear magnetic resonance spectroscopy, measured the relaxation times and diffusion coefficient of water protons in primary mammary adenocarcinomas of mice. In our biological model, three morphological stages were defined: (a) mammary gland tissue from pregnant mice, (b) preneoplastic nodules, and (c) neoplastic tissue. It was found that neoplastic tissues could be dis...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2016