Convergence and reliability of the Rehr-Albers formalism in multiple-scattering calculations of photoelectron diffraction

被引:124
作者
Chen, Y [1 ]
de Abajo, FJG
Chasse, A
Ynzunza, RX
Kaduwela, AP
Van Hove, MA
Fadley, CS
机构
[1] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA
[2] Univ Basque Country, EHU, Fac Informat, Dept CCIA, E-20080 San Sebastian, Spain
[3] Univ Halle Wittenberg, Dept Phys, D-06099 Halle, Germany
[4] Univ Calif Davis, Dept Phys, Livermore, CA 95616 USA
关键词
D O I
10.1103/PhysRevB.58.13121
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The Rehr-Albers (RA) separable Green's-function formalism, which is based on an expansion series, has been successful in speeding up multiple-scattering cluster calculations for photoelectron diffraction simulations, particularly in its second-order version. The performance of this formalism is explored here in terms of computational speed, convergence over orders of multiple scattering, over orders of approximation, and over cluster size, by comparison with exact cluster-based formalisms. It is found that the second-order RA approximation [characterized by (6x6) scattering matrices] is adequate for many situations, particularly if the initial state from which photoemission occurs is of s or p type. For the most general and quantitative applications, higher-order versions of RA may become necessary for d initial states [third-order, i.e., (10x 10) matrices] and f initial states [fourth-order, i.e., (15x15) matrices]. However, the required RA order decreases as an electron wave proceeds along a multiple-scattering path, and this can be exploited, together with the selective and automated cutoff of weakly contributing matrix elements and paths, to yield computer time savings of at least an order of magnitude with no significant loss of accuracy. Cluster sizes of up to approximately 100 atoms should be sufficient for most problems that require about 5% accuracy in diffracted intensities. Excellent sensitivity to structure is seen in comparisons of second-order theory with variable geometry to exact theory as a fictitious "experiment." Our implementation of the Rehr-Albers formalism thus represents a versatile, quantitative, and efficient method for the accurate simulation of photoelectron diffraction. [S0163-1829(98)04943-1].
引用
收藏
页码:13121 / 13131
页数:11
相关论文
共 60 条
[1]  
BAIRD RJ, 1977, PHYS REV B, V15, P666, DOI 10.1103/PhysRevB.15.666
[2]   PHOTOELECTRON HOLOGRAPHY [J].
BARTON, JJ .
PHYSICAL REVIEW LETTERS, 1988, 61 (12) :1356-1359
[3]   REMOVING MULTIPLE-SCATTERING AND TWIN IMAGES FROM HOLOGRAPHIC IMAGES [J].
BARTON, JJ .
PHYSICAL REVIEW LETTERS, 1991, 67 (22) :3106-3109
[4]   CURVED-WAVE-FRONT CORRECTIONS FOR PHOTOELECTRON SCATTERING [J].
BARTON, JJ ;
SHIRLEY, DA .
PHYSICAL REVIEW B, 1985, 32 (04) :1892-1905
[5]   SMALL-ATOM APPROXIMATIONS FOR PHOTOELECTRON SCATTERING IN THE INTERMEDIATE-ENERGY RANGE [J].
BARTON, JJ ;
SHIRLEY, DA .
PHYSICAL REVIEW B, 1985, 32 (04) :1906-1920
[6]  
BARTON JJ, THESIS U CALIFORNIA
[7]   RENORMALIZED MULTIPLE-SCATTERING THEORY OF PHOTOELECTRON DIFFRACTION [J].
BIAGINI, M .
PHYSICAL REVIEW B, 1993, 48 (05) :2974-2980
[8]   THEORY OF PHOTOELECTRON DIFFRACTION IN A COULOMB FIELD [J].
BIAGINI, M .
PHYSICAL REVIEW B, 1992, 46 (17) :10588-10593
[9]   STUDIES OF ADSORBED MOLECULES BY X-RAY PHOTOELECTRON DIFFRACTION (XPD) [J].
BONZEL, HP .
PROGRESS IN SURFACE SCIENCE, 1993, 42 (1-4) :219-229
[10]   EPITAXIAL FILM CRYSTALLOGRAPHY BY HIGH-ENERGY AUGER AND X-RAY PHOTOELECTRON DIFFRACTION [J].
CHAMBERS, SA .
ADVANCES IN PHYSICS, 1991, 40 (04) :357-415