Results for “CsCo(CO)4” | Engineering Papers

DOE OSTI2020

Materials Data on CsCo(CO)4 by Materials Project

CsCo(CO)4 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. Cs1+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Cs–O bond lengths are 3.24 Å. Co1+ is bonded in a tetrahedral geometry to four equivalent C+1.50+ atoms. All Co–C bond lengths are 1.74 Å. C+1.50+ is bonded in a linear geometry to one Co1+ and one O2- atom. The C–O bond length is 1.18 Å. O2- is bonded in a distorted single-bond geometry to one Cs1+ and one C+1.50+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2023

Field tunable magnetic transitions of CsCo 2 (MoO 4 ) 2 (OH): a triangular chain structure with a frustrated geometry

The sawtooth chain compound CsCo 2 (MoO 4 ) 2 (OH) is a complex magnetic system and here, we present a comprehensive series of magnetic and neutron scattering measurements to determine its magnetic phase diagram. The magnetic properties of CsCo 2 (MoO 4 ) 2 (OH) exhibit a strong coupling to the crystal lattice and its magnetic ground state can be easily manipulated by applied magnetic fields. There are two unique Co 2+ ions, base and vertex, with J bb and J bv magnetic exchange. The magnetism is highly anisotropic with the b-axis (chain) along the easy axis and the material orders antiferromagnetically at T N = 5 K. There are two successive metamagnetic transitions, the first at H c 1 = 0.2 kOe into a ferrimagnetic structure, and the other at H c 2 = 20 kOe to a ferromagnetic phase. Heat capacity measurements in various fields support the metamagnetic phase transformations, and the magnetic entropy value is intermediate between S = 3/2 and 1/2 states. The zero field antiferromagnetic phase contains vertex magnetic vectors (Co(1)) aligned parallel to the b-axis, while the base vectors (Co(2)) are canted by 34° and aligned in an opposite direction to the vertex vectors. The spins in parallel adjacent chains align in opposite directions, creating an overall antiferromagnetic structure. Further, at a 3 kOe applied magnetic field, adjacent chains flip by 180° to generate a ferrimagnetic phase. An increase in field gradually induces the Co(1) moment to rotate along the b-axis and align in the same direction with Co(2) generating a ferromagnetic structure. The antiferromagnetic exchange parameters are calculated to be J bb = 0.028 meV and J bv = 0.13 meV, while the interchain exchange parameter is considerably weaker at J ch = (0.0047/N ch ) meV. Our results demonstrate that the CsCo 2 (MoO 4 ) 2 (OH) is a promising candidate to study new physics associated with sawtooth chain magnetism and it encourages further theoretical studies as well as the synthesis of other sawtooth chain structures with different magnetic ions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Materials Data on CsCoH24(C7N4)2 by Materials Project

CsCo(CN)6(N(CH3)4)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional and consists of four tetramethylammonium molecules and one CsCo(CN)6 framework. In the CsCo(CN)6 framework, Cs1+ is bonded in an octahedral geometry to six N3- atoms. There are four shorter (3.69 Å) and two longer (3.73 Å) Cs–N bond lengths. Co1+ is bonded in an octahedral geometry to six C+0.14- atoms. All Co–C bond lengths are 1.88 Å. There are two inequivalent C+0.14- sites. In the first C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–N bond length is 1.18 Å. In the second C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–N bond length is 1.18 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a single-bond geometry to one Cs1+ and one C+0.14- atom. In the second N3- site, N3- is bonded in a single-bond geometry to one Cs1+ and one C+0.14- atom.

36 MATERIALS SCIENCE↗