ORIENTATIONAL PROBING OF POLYMERIC THIN-FILMS BY NEXAFS - CALCULATIONS ON POLYTETRAFLUOROETHYLENE

被引：30
作者：
AGREN, H
CARRAVETTA, V
VAHTRAS, O
PETTERSSON, LGM
机构：
[1] CNR,IST CHIM QUANTIST & ENERGET MOLEC,I-56100 PISA,ITALY
[2] UNIV STOCKHOLM,INST PHYS,S-11346 STOCKHOLM,SWEDEN
来源：
PHYSICAL REVIEW B | 1995年 / 51卷 / 24期
关键词：
D O I：
10.1103/PhysRevB.51.17848
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
We demonstrate the possibility for orientational probing of polymeric thin films by means of computer simulations of near-edge x-ray-absorption fine structure spectra. Using a recently developed algorithm for static exchange calculations of core-excited states we study the near-edge carbon and fluorine K absorption in polytetrafluoroethylene. Unpolarized and polarization-selected results for oligomers including up to five fluoroethylene subunits are presented. Through experimental comparision we confirm that the polytetrafluoroethylene (Teflon) polymer sample used in previous experimental studies is highly oriented, that the zig-zag structure prevails over the helical structure, and that the polymer chain is directed along the assumed slide direction. It is shown how experimental information can be used to determine if the carbon plane is perpendicular or orthogonal to the substrate surface. © 1995 The American Physical Society.
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页码：17848 / 17855
页数：8
相关论文
共 22 条
[1]   DIRECT, ATOMIC ORBITAL, STATIC EXCHANGE CALCULATIONS OF PHOTOABSORPTION SPECTRA OF LARGE MOLECULES AND CLUSTERS [J].
AGREN, H ;
CARRAVETTA, V ;
VAHTRAS, O ;
PETTERSSON, LGM .
CHEMICAL PHYSICS LETTERS, 1994, 222 (1-2) :75-81
[2]   ORIGIN OF FINE-STRUCTURE IN THE VICINITY OF THE K-EDGES IN THE CO ELECTRON-ENERGY LOSS SPECTRA [J].
AGREN, H ;
ARNEBERG, R .
PHYSICA SCRIPTA, 1984, 30 (01) :55-58
[3]   PRINCIPLES FOR A DIRECT SCF APPROACH TO LCAO-MO ABINITIO CALCULATIONS [J].
ALMLOF, J ;
FAEGRI, K ;
KORSELL, K .
JOURNAL OF COMPUTATIONAL CHEMISTRY, 1982, 3 (03) :385-399
[4]   SCANNING-TUNNELING-MICROSCOPY STUDY OF ORIENTED POLY(TETRAFLUOROETHYLENE) SUBSTRATES [J].
BODO, P ;
ZIEGLER, C ;
RASMUSSON, JR ;
SALANECK, WR ;
CLARK, DT .
SYNTHETIC METALS, 1993, 55 (01) :329-334
[5]   NEAR-EDGE CORE PHOTOABSORPTION IN POLYENES [J].
CARRAVETTA, V ;
AGREN, H ;
PETTERSSON, LGM ;
VAHTRAS, O .
JOURNAL OF CHEMICAL PHYSICS, 1995, 102 (14) :5589-5597
[6]   DETERMINATION OF SURFACE-STRUCTURE AND ORIENTATION OF POLYMERIZED TETRAFLUOROETHYLENE FILMS BY NEAR-EDGE X-RAY ABSORPTION FINE-STRUCTURE, X-RAY PHOTOELECTRON-SPECTROSCOPY, AND STATIC SECONDARY ION MASS-SPECTROMETRY [J].
CASTNER, DG ;
LEWIS, KB ;
FISCHER, DA ;
RATNER, BD ;
GLAND, JL .
LANGMUIR, 1993, 9 (02) :537-542
[7]  
DEWAR MJS, 1961, J AM CHEM SOC, V99, P4899
[8]   NEAR EDGE X-RAY-ABSORPTION FINE-STRUCTURE DETERMINATION OF ALKYL-CHAIN ORIENTATION - BREAKDOWN OF THE BUILDING-BLOCK SCHEME [J].
HAHNER, G ;
KINZLER, M ;
WOLL, C ;
GRUNZE, M ;
SCHELLER, MK ;
CEDERBAUM, LS .
PHYSICAL REVIEW LETTERS, 1991, 67 (07) :851-854
[9]  
HAHNER G, 1992, J VAC SCI TECHNOL A, V10, P2758, DOI 10.1116/1.577906
[10]   THE SIGMA-STAR MOLECULAR-ORBITALS OF PERFLUOROALKANES AS STUDIED BY INNER-SHELL ELECTRON-ENERGY LOSS AND ELECTRON TRANSMISSION SPECTROSCOPIES [J].
ISHII, I ;
MCLAREN, R ;
HITCHCOCK, AP ;
JORDAN, KD ;
CHOI, Y ;
ROBIN, MB .
CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE, 1988, 66 (08) :2104-2121
123