A perturbation basis for calculating NMR Diffusometry

摘要: An approximative method for solving the Bloch-Torrey equation in general porous media is presented. The expand boundaries defining using electrostatic charges. As a result eigenvalue problem of Laplace operator confined geometry can approximately solved. Importantly solution orthogonal low-frequent region Fourier space. This gives natural approach studying spin magnetization presence magnetic fields. error approximation scales with N^{-2} times magnitude each eigenvalue, where N size expansion matrix. From computational point view, calculations scale quadratically number basis functions fast multipole methods.