Abstract
When establishing the feasibility of matching experimental and theoretical convergent-beam electron diffraction (CBED) patterns to recover structure-factor information it is important to investigate the accuracy of the results obtained and the effects of random and systematic errors. The effects of counting noise in a digital data-collection system are studied, together with various sources of systematic error. The sensitivity of parts of the pattern to specific structure-factor parameters is analysed via the calculation of analytic gradients of the intensity with respect to those parameters. All calculations are based on diffraction at the [110] axis of GaP, using simulated CBED patterns as idealised "experimental" data. The results indicate that, provided care is taken to minimise the effects of systematic errors, low-order structure factors may be extracted from experimental data with an accuracy approaching 0.1%.
| Original language | English |
|---|---|
| Pages (from-to) | 241-251 |
| Number of pages | 11 |
| Journal | Ultramicroscopy |
| Volume | 45 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Sep 1992 |
| Externally published | Yes |
Cite this
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Sensitivity and accuracy of CBED pattern-matching. / BIRD, DM; SAUNDERS, M.
In: Ultramicroscopy, Vol. 45, No. 2, 09.1992, p. 241-251.Research output: Contribution to journal › Article
TY - JOUR
T1 - Sensitivity and accuracy of CBED pattern-matching
AU - BIRD, DM
AU - SAUNDERS, M
PY - 1992/9
Y1 - 1992/9
N2 - When establishing the feasibility of matching experimental and theoretical convergent-beam electron diffraction (CBED) patterns to recover structure-factor information it is important to investigate the accuracy of the results obtained and the effects of random and systematic errors. The effects of counting noise in a digital data-collection system are studied, together with various sources of systematic error. The sensitivity of parts of the pattern to specific structure-factor parameters is analysed via the calculation of analytic gradients of the intensity with respect to those parameters. All calculations are based on diffraction at the [110] axis of GaP, using simulated CBED patterns as idealised "experimental" data. The results indicate that, provided care is taken to minimise the effects of systematic errors, low-order structure factors may be extracted from experimental data with an accuracy approaching 0.1%.
AB - When establishing the feasibility of matching experimental and theoretical convergent-beam electron diffraction (CBED) patterns to recover structure-factor information it is important to investigate the accuracy of the results obtained and the effects of random and systematic errors. The effects of counting noise in a digital data-collection system are studied, together with various sources of systematic error. The sensitivity of parts of the pattern to specific structure-factor parameters is analysed via the calculation of analytic gradients of the intensity with respect to those parameters. All calculations are based on diffraction at the [110] axis of GaP, using simulated CBED patterns as idealised "experimental" data. The results indicate that, provided care is taken to minimise the effects of systematic errors, low-order structure factors may be extracted from experimental data with an accuracy approaching 0.1%.
KW - ELECTRON-DIFFRACTION
U2 - 10.1016/0304-3991(92)90512-I
DO - 10.1016/0304-3991(92)90512-I
M3 - Article
VL - 45
SP - 241
EP - 251
JO - Ultramicroscopy
JF - Ultramicroscopy
SN - 0304-3991
IS - 2
ER -