4 research outputs found
4-Phenoxyphenol: A Porous Molecular Material
4-Phenoxyphenol is a simple organic molecule that crystallizes
as a porous material with channels running throughout the structure.
The channels are constructed by a 6-fold hydrogen bonded ring and
can host solvent molecules incorporated during crystal growth, with
a minimum channel diameter of 5.8ā5.9 Ć
; each channel
usually contains a single solvent molecule per unit cell. The hydrogen
bonded ring shows surprising flexibility, being able both to <i>breathe</i> and to sustain its crystalline integrity even when
grown with empty pores. This is particularly surprising given that
the remainder of the interactions within the crystal structure are
CāHĀ·Ā·Ā·Ļ interactions and are weak in nature.
It is also possible to grow ādryā porous 4-phenoxyphenol
crystals by using a bulky solvent in the recrystallization
The Role of OrderāDisorder Transitions in the Quest for Molecular Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence Iron(II)āIron(III) Formate Framework
Neutron
diffraction studies have been carried out to shed light
on the unprecedented orderādisorder phase transition (ca. 155
K) observed in the mixed-valence ironĀ(II)āironĀ(III) formate
framework compound [NH<sub>2</sub>(CH<sub>3</sub>)<sub>2</sub>]<sub><i>n</i></sub>[Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub>. The crystal structure at 220
K was first determined from Laue diffraction data, then a second refinement
at 175 K and the crystal structure determination in the low temperature
phase at 45 K were done with data from the monochromatic high resolution
single crystal diffractometer D19. The 45 K nuclear structure reveals
that the phase transition is associated with the orderādisorder
of the dimethylammonium counterion that is weakly anchored in the
cavities of the [Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub> framework. In the low-temperature
phase, a change in space group from <i>P</i>3Ģ
1<i>c</i> to <i>R</i>3Ģ
<i>c</i> occurs,
involving a tripling of the <i>c</i>-axis due to the ordering
of the dimethylammonium counterion. The occurrence of this nuclear
phase transition is associated with an electric transition, from paraelectric
to antiferroelectric. A combination of powder and single crystal neutron
diffraction measurements below the magnetic order transition (ca.
37 K) has been used to determine unequivocally the magnetic structure
of this NeĢel N-Type ferrimagnet, proving that the ferrimagnetic
behavior is due to a noncompensation of the different Fe<sup>II</sup> and Fe<sup>III</sup> magnetic moments
The Role of OrderāDisorder Transitions in the Quest for Molecular Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence Iron(II)āIron(III) Formate Framework
Neutron
diffraction studies have been carried out to shed light
on the unprecedented orderādisorder phase transition (ca. 155
K) observed in the mixed-valence ironĀ(II)āironĀ(III) formate
framework compound [NH<sub>2</sub>(CH<sub>3</sub>)<sub>2</sub>]<sub><i>n</i></sub>[Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub>. The crystal structure at 220
K was first determined from Laue diffraction data, then a second refinement
at 175 K and the crystal structure determination in the low temperature
phase at 45 K were done with data from the monochromatic high resolution
single crystal diffractometer D19. The 45 K nuclear structure reveals
that the phase transition is associated with the orderādisorder
of the dimethylammonium counterion that is weakly anchored in the
cavities of the [Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub> framework. In the low-temperature
phase, a change in space group from <i>P</i>3Ģ
1<i>c</i> to <i>R</i>3Ģ
<i>c</i> occurs,
involving a tripling of the <i>c</i>-axis due to the ordering
of the dimethylammonium counterion. The occurrence of this nuclear
phase transition is associated with an electric transition, from paraelectric
to antiferroelectric. A combination of powder and single crystal neutron
diffraction measurements below the magnetic order transition (ca.
37 K) has been used to determine unequivocally the magnetic structure
of this NeĢel N-Type ferrimagnet, proving that the ferrimagnetic
behavior is due to a noncompensation of the different Fe<sup>II</sup> and Fe<sup>III</sup> magnetic moments
The Role of OrderāDisorder Transitions in the Quest for Molecular Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence Iron(II)āIron(III) Formate Framework
Neutron
diffraction studies have been carried out to shed light
on the unprecedented orderādisorder phase transition (ca. 155
K) observed in the mixed-valence ironĀ(II)āironĀ(III) formate
framework compound [NH<sub>2</sub>(CH<sub>3</sub>)<sub>2</sub>]<sub><i>n</i></sub>[Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub>. The crystal structure at 220
K was first determined from Laue diffraction data, then a second refinement
at 175 K and the crystal structure determination in the low temperature
phase at 45 K were done with data from the monochromatic high resolution
single crystal diffractometer D19. The 45 K nuclear structure reveals
that the phase transition is associated with the orderādisorder
of the dimethylammonium counterion that is weakly anchored in the
cavities of the [Fe<sup>III</sup>Fe<sup>II</sup>(HCOO)<sub>6</sub>]<sub><i>n</i></sub> framework. In the low-temperature
phase, a change in space group from <i>P</i>3Ģ
1<i>c</i> to <i>R</i>3Ģ
<i>c</i> occurs,
involving a tripling of the <i>c</i>-axis due to the ordering
of the dimethylammonium counterion. The occurrence of this nuclear
phase transition is associated with an electric transition, from paraelectric
to antiferroelectric. A combination of powder and single crystal neutron
diffraction measurements below the magnetic order transition (ca.
37 K) has been used to determine unequivocally the magnetic structure
of this NeĢel N-Type ferrimagnet, proving that the ferrimagnetic
behavior is due to a noncompensation of the different Fe<sup>II</sup> and Fe<sup>III</sup> magnetic moments