Single-crystal-to-single-crystal transformations triggered by dehydration in polyoxometalate-based compounds

Single-crystal-to-single-crystal transformations are solid-state phase transitions between different crystalline states in which the crystal integrity and the long-range structural order are retained through the whole transformation process. Such a phenomenon constitutes the structural response that some compounds afford when being exposed to a given external stimulus (temperature, pressure, light, etc.) and, therefore, its study has become a relevant focus of interest within crystal engineering because it allows for monitoring how certain properties (colour, magnetism, luminescence, porosity) of the stimuli-responsive material are modified as the structure evolves into the activated form. A range of organic, inorganic and hybrid systems have been found to undergo such phase transitions, but these examples only include a small number of compounds that incorporate polyoxometalate anions, among which the removal of guest solvent molecules (dehydration) stands out as the most common external stimulus able to induce the occurrence of a single-crystal-to-single-crystal transformation. This feature article compiles the examples of dehydration-triggered single-crystal-to-single-crystal transformation studies that have been reported to date for polyoxometalate-based compounds and reviews some of their most relevant structural aspects.

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Solvent vapour induced rare single-crystal-to-single-crystal transformation of stimuli-responsive fluorophore: Solid state fluorescence tuning, switching and role of molecular conformation and substituents

Dyes and Pigments ◽

10.1016/j.dyepig.2019.108067 ◽

2020 ◽

Vol 174 ◽

pp. 108067

Author(s):

Palamarneri Sivaraman Hariharan ◽

Chengjun Pan ◽

Subramanian Karthikeyan ◽

Dexun Xie ◽

Akira Shinohara ◽

...

Keyword(s):

Solid State ◽

Single Crystal ◽

Molecular Conformation ◽

Stimuli Responsive ◽

Solvent Vapour ◽

Crystal Transformation ◽

Solid State Fluorescence

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Analysis of rapidly synthesized guest-filled porous complexes with synchrotron radiation: practical guidelines for the crystalline sponge method

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314019573 ◽

2015 ◽

Vol 71 (1) ◽

pp. 46-58 ◽

Cited By ~ 51

Author(s):

Timothy R. Ramadhar ◽

Shao-Liang Zheng ◽

Yu-Sheng Chen ◽

Jon Clardy

Keyword(s):

Synchrotron Radiation ◽

Single Crystal ◽

Metal Organic Framework ◽

Transformation Process ◽

Quality Data ◽

High Quality Data ◽

Crystal Transformation ◽

Practical Guidelines ◽

Metal Organic ◽

Using Data

A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collection times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flackxabsolute stereochemical determination parameter to date for these systems. The structures did not require the use ofPLATON/SQUEEZEor other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of reliable high-quality data, and will allow construction of chemically and physically sensible models for guest structural determination.

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Single crystal to single crystal transformation of spin-crossover coordination polymers from 3D frameworks to 2D layers

Journal of Materials Chemistry C ◽

10.1039/d1tc00470k ◽

2021 ◽

Vol 9 (15) ◽

pp. 5082-5087

Author(s):

Yu Gong ◽

Wang-Kang Han ◽

Hui-Shu Lu ◽

Qing-Tao Hu ◽

Huan Tu ◽

...

Keyword(s):

Magnetic Properties ◽

Single Crystal ◽

Coordination Polymers ◽

Ligand Exchange ◽

Spin Crossover ◽

Metal Organic Frameworks ◽

Crystal Transformation ◽

Metal Organic

New Hofmann-type metal–organic frameworks display rare and complete ligand exchange induced single crystal to single crystal transformations from 3D frameworks to 2D layers, accompanied by magnetic properties transition from two-step SCO behavior to hysteretic SCO behavior.

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Solid-State Conformational Flexibility at Work: Energetic Landscape of a Single Crystal-to-Single Crystal Transformation in a Cyclic Hexapeptoid

Crystal Growth & Design ◽

10.1021/acs.cgd.0c01244 ◽

2021 ◽

Vol 21 (2) ◽

pp. 897-907

Author(s):

Giovanni Pierri ◽

Marta Corno ◽

Eleonora Macedi ◽

Maria Voccia ◽

Consiglia Tedesco

Keyword(s):

Solid State ◽

Single Crystal ◽

Conformational Flexibility ◽

Crystal Transformation

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Complex structure and Mössbauer effect observed in the course of phase transitions in PbZr0.72Sn0.28O3 single crystal

The Journal of Chemical Physics ◽

10.1063/5.0032957 ◽

2020 ◽

Vol 153 (22) ◽

pp. 224202

Author(s):

Irena Jankowska-Sumara ◽

Mariola Kądziołka-Gaweł ◽

Maria Podgórna ◽

Andrzej Majchrowski ◽

Krystian Roleder

Keyword(s):

Phase Transitions ◽

Single Crystal ◽

Mössbauer Effect ◽

Complex Structure ◽

Mossbauer Effect

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Retention of a Four-Fold Interpenetrating Cadmium–Organic Framework through a Three-Step Single Crystal Transformation

Inorganic Chemistry ◽

10.1021/acs.inorgchem.1c01105 ◽

2021 ◽

Author(s):

Jia-Qian Li ◽

Si-Wen Ke ◽

Tong Yan ◽

Yu-Yang Li ◽

Yan Zhou ◽

...

Keyword(s):

Single Crystal ◽

Crystal Transformation ◽

Organic Framework

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The Influence of Wire Speed on Phase Transitions and Residual Stress in Single Crystal Silicon Wafers Sawn by Resin Bonded Diamond Wire Saw

Micromachines ◽

10.3390/mi12040429 ◽

2021 ◽

Vol 12 (4) ◽

pp. 429

Author(s):

Tengyun Liu ◽

Peiqi Ge ◽

Wenbo Bi

Keyword(s):

Residual Stress ◽

Surface Layer ◽

Phase Transitions ◽

Single Crystal ◽

Amorphous Silicon ◽

Silicon Wafer ◽

Single Crystal Silicon ◽

Silicon Wafers ◽

Crystal Silicon ◽

Diamond Wire

Lower warp is required for the single crystal silicon wafers sawn by a fixed diamond wire saw with the thinness of a silicon wafer. The residual stress in the surface layer of the silicon wafer is the primary reason for warp, which is generated by the phase transitions, elastic-plastic deformation, and non-uniform distribution of thermal energy during wire sawing. In this paper, an experiment of multi-wire sawing single crystal silicon is carried out, and the Raman spectra technique is used to detect the phase transitions and residual stress in the surface layer of the silicon wafers. Three different wire speeds are used to study the effect of wire speed on phase transition and residual stress of the silicon wafers. The experimental results indicate that amorphous silicon is generated during resin bonded diamond wire sawing, of which the Raman peaks are at 178.9 cm−1 and 468.5 cm−1. The ratio of the amorphous silicon surface area and the surface area of a single crystal silicon, and the depth of amorphous silicon layer increases with the increasing of wire speed. This indicates that more amorphous silicon is generated. There is both compressive stress and tensile stress on the surface layer of the silicon wafer. The residual tensile stress is between 0 and 200 MPa, and the compressive stress is between 0 and 300 MPa for the experimental results of this paper. Moreover, the residual stress increases with the increase of wire speed, indicating more amorphous silicon generated as well.

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