N2–O2 Icing in Single-Crystal In-House X-ray Diffraction Experiments Using an Open-Flow Helium Cryostat Full article
| Journal |
Journal of Applied Crystallography
ISSN: 0021-8898 , E-ISSN: 1600-5767 |
||||||
|---|---|---|---|---|---|---|---|
| Output data | Year: 2021, Volume: 54, Pages: 1271-1275 Pages count : 5 DOI: 10.1107/S1600576721006440 | ||||||
| Tags | helium open-flow cryostat; cryocrystallography; single-crystal X-ray diffraction; icing | ||||||
| Authors |
|
||||||
| Affiliations |
|
Funding (3)
| 1 | Ministry of Science and Higher Education of the Russian Federation | 0239-2021-0002 |
| 2 | Universitat Wien | BE532003 |
| 3 | FWF Austrian Science Fund | P 29149-N29 |
Abstract:
This note reports a study of the coating of a crystal with ‘ice’ at temperatures below 45 K during single-crystal in-house diffraction experiments when using an open-flow helium cryostat. The ‘ice’ consists mainly of crystalline oxygen and
nitrogen. This suggests completely different techniques for avoiding this type of icing compared with water icing. With appropriate choices of crystal mount, crystal position with respect to the nozzle and gas flow conditions, it is possible
to avoid detectable condensation. However, sometimes this can not be achieved in practice (poor diffraction from a smaller crystal, necessity of positioning the crystal in certain orientations to achieve desired data completeness, need to reduce helium consumption etc.). The problem of icing seems to be less common for powder experiments where the laminar gas flow is parallel to the capillary containing the sample, and for synchrotron experiments where the sample is comparably small and almost continuously rotated, which facilitates the ice covering being removed by the gas flow. This last technique can in principle also be applied to single-crystal X-ray diffraction using laboratory diffractometers – periodic rapid rotation of the crystal can help to minimize any icing, but this technique will not work when the condensation rate is comparable with or faster than one frame of data collection. The coating around a sample crystal not only reduces the quality of the diffraction data, but the temperature at the sample below the coating may also differ significantly from that at the cryostat nozzle reported by the instrument.
Cite:
Zakharov B.A.
, Miletich R.
, Bogdanov N.E.
, Boldyreva E.V.
N2–O2 Icing in Single-Crystal In-House X-ray Diffraction Experiments Using an Open-Flow Helium Cryostat
Journal of Applied Crystallography. 2021. V.54. P.1271-1275. DOI: 10.1107/S1600576721006440 WOS Scopus РИНЦ AN OpenAlex
N2–O2 Icing in Single-Crystal In-House X-ray Diffraction Experiments Using an Open-Flow Helium Cryostat
Journal of Applied Crystallography. 2021. V.54. P.1271-1275. DOI: 10.1107/S1600576721006440 WOS Scopus РИНЦ AN OpenAlex
Dates:
| Submitted: | Mar 12, 2021 |
| Accepted: | Jun 21, 2021 |
| Published online: | Jul 29, 2021 |
| Published print: | Aug 1, 2021 |
Identifiers:
| Web of science: | WOS:000683118400027 |
| Scopus: | 2-s2.0-85120962822 |
| Elibrary: | 47541407 |
| Chemical Abstracts: | 2021:1771408 |
| OpenAlex: | W3188806204 |