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Single crystals of a new transition metal adelite-descloizite-type structure were synthesized using a high temperature (580 °C) high-pressure hydrothermal technique. Single crystal X-ray diffraction and energy dispersive X-ray analysis (EDX) were used to investigate the structure and elemental composition, respectively. SrNi(VO4)(OH) crystallizes in an acentric orthorhombic crystal system in the space group P212121 (no. 19); Z = 4, a = 5.9952(4) Å, b = 7.5844(4) Å, c = 9.2240(5) Å. The structure is comprised of a Ni–O–V framework where Sr2+ ions reside inside the channels. Single-crystal magnetic measurements display a significant anisotropy in both temperature- and field-dependent data. The temperature dependent magnetic measurement shows antiferromagnetic behavior at TN~8 K. Overall, the magnetic properties indicate the presence of competing antiferromagnetic and ferromagnetic interactions of SrNi(VO4)(OH).
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This content will become publicly available on January 7, 2026
Surface structure characterization of rubrene(001) single crystal with sum frequency generation spectroscopy and reflection high-energy electron diffraction
Rubrene is one of the leading organic semiconductors in scientific and industrial research, showing good conductivities and utilities in devices such as organic field-effect transistors. In these applications, the rubrene crystals often contact ionic liquids and other materials. Consequently, their surface properties and interfacial interactions influence the device’s performance. Although rubrene has been extensively studied with multiple structure characterization techniques, a complete description of the structure of rubrene single-crystal surfaces at the molecular level remains elusive. This study elucidates the molecular orientation and arrangement on the surface of rubrene single crystals with sum frequency generation (SFG) spectroscopy and reflection high-energy electron diffraction, respectively. The results confirm the near-surface unit cells with in-plane lattice parameters of a = 7.24 Å and b = 14.3 Å and an out-of-plane constant of c = 26.9 Å. Furthermore, the SFG analysis yields the tilt and rotation angles of θ = 15° and φ = 43° with respect to the crystalline c and a axes, respectively, and an in-plane twist of ψ = 3° for the surface phenyl rings.
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- PAR ID:
- 10618068
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 162
- Issue:
- 1
- ISSN:
- 0021-9606
- Page Range / eLocation ID:
- 014701
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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