Mechanochemical synthesis of<i>N</i>-salicylideneaniline: thermosalient effect of polymorphic crystals

Mittapalli, Sudhir; Perumalla, D. Sravanakumar; Nangia, Ashwini

doi:10.1107/s2052252517004043

Cited by 34 publications

(36 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The effect was first noted in 1983, and after a long hiatus, it was explored in greater detail in the anticholinergic agent oxitropium bromide in 2010 . Encouraged by these studies, over 20 new examples have been reported in the last decade that are categorized in three classes based on their structures, with a number of notable reports of serendipitous observations increasing in the past several years . It has also been demonstrated that the rates of the TS phase transitions are several orders of magnitude faster than other, more common solid–solid transitions .…”

Section: Introductionmentioning

confidence: 99%

Global Performance Indices for Dynamic Crystals as Organic Thermal Actuators

Karothu

Halabi

et al. 2020

Advanced Materials

View full text Add to dashboard Cite

same basic thermodynamic principles of energy transduction and are collectively referred to as actuators. [1][2][3][4][5][6][7][8][9][10] While complex natural biomechanical systems have evolved to aid functions such as dispersal and survival, the artificially manufactured actuators are specifically designed for integration in mechatronic or adaptronic systems that range from miniature devices such as navigation and positioning systems in flying machines, to complex systems that can perform tasks in specific environments, such as humanoid robots and spacecraft. The current applications of actuators are many and diverse; they include sensors, [11,12] artificial muscles, [13] soft robotics, [14] and energy-harvesting materials. [15] Simple or complex actuating motions can be induced by heat, light, electricity, pressure, and moisture, among other stimuli, and can be realized with shape-memory polymers, [16] conductive fibers, [17] liquid crystal elastomers, [18] piezoelectric, [19] magnetostrictive, [20] and electromagnetic materials. [21] The energy supplied to the artificial actuators can vary from fluid pressure or flow in the pneumatics, to current, charge or voltage in the electromagnetic, piezoelectric and magnetostrictive actuators, to heat in shape memory and thermal expansion actuators.The active media in actuators include fluids, hard solids such as metals, and even complex soft matter such as tissuesensembles of cells with similar structure that act together to perform a specific function. While molecular crystals do not immediately appeal as working actuating medium, their dynamic properties have recently transpired as an alternative to other materials and they are thought to hold an untapped potential for miniature, soft actuating devices, quickly shaping up into a new research field, crystal adaptronics. [22,23] Smallscale demonstrations of the usefulness of molecular crystals as microscale devices, including cantilevers, [24,25] ratchets, [26] optical waveguides, [27][28][29][30][31][32][33][34][35][36] and other "crystal gears" [37] that can move or reshape are occasionally reported for dynamic crystals. Although being very illustrative, these demonstrations have thus far remained limited to a laboratory scale and have not been implemented in actual, functional devices. Some of the obstacles toward wider applications are difficulties with reproducible growth of crystals of predictable size without the use Crystal adaptronics is an emergent materials science discipline at the intersection of solid-state chemistry and mechanical engineering that explores the dynamic nature of mechanically reconfigurable, motile, and explosive crystals. Adaptive molecular crystals bring to materials science a qualitatively new set of properties that associate long-range structural order with softness and mechanical compliance. However, the full potential of this class of materials remains underexplored and they have not been considered as materials of choice in an engineer's toolbox. A set of general performance metric...

show abstract

Section: Introductionmentioning

confidence: 99%

Global Performance Indices for Dynamic Crystals as Organic Thermal Actuators

Karothu

Halabi

et al. 2020

Advanced Materials

View full text Add to dashboard Cite

show abstract

“…The meltw as cooled, and the solid material also movedw hile solidifying. [2][3][4][5][6][7][8][9][10][11] In contrastwith form I, crystals of form III did not show motion, as determined by HSM, and thus, this polymorph was determined not to be thermosalienta bove room temperature. Af ew crystals that did not jump melted at ah igher temperature ( Figure 1B).…”

Section: Resultsmentioning

confidence: 90%

“…As no chemical decomposition such as evolution of gas could be observed, this behavior was ac lear signature of the thermosalient effect, ap henomenon by which crystals acquire momentum and move or burst owing to sudden release of the elastic energy accumulated during af irst-order,m artensitic-like phase transition. [2][3][4][5][6][7][8][9][10][11] In contrastwith form I, crystals of form III did not show motion, as determined by HSM, and thus, this polymorph was determined not to be thermosalienta bove room temperature. Regrettably,f urther thermal and microscopy characterization of crystalso ff ormII, the disappearing polymorph of 2,was not possible owing to their paucity.…”

Section: Resultsmentioning

confidence: 90%

“…Since its first observation, [1] the thermosalient effect-visually striking motion of crystals, whereby they are self-actuated and move rapidly owing to sudden release of strain-was and has remained as erendipitously observed phenomenon. [2][3][4][5][6][7][8][9][10][11][12][13] Early reports of this effect, which occursa saresult of am artensitictype structuralp hase transition, were without exceptiona result of carefulo bservation of crystals during measurement of their melting points, by which point some crystalsw eref ound to "jump"u pon heating in ac apillary or on ah ot stage.S ome of the modern sophisticated methods to determine the melting point or to record thermoanalytical curves by differential scanningc alorimetry (DSC) require crystals to be powdered and/or closed in the sample holder of the instrument. As in either case the sample is visually inaccessible, the thermosalient phenomenon mayh ave been overlooked because any changes in the appearance of the sample during heating could not be visually observed.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Crystal Packing on the Thermosalient Effect of the Pincer‐Type Diester Naphthalene‐2,3‐diyl‐bis(4‐fluorobenzoate): A New Class II Thermosalient Solid

Tamboli

Karothu

Shashidhar

et al. 2018

Chemistry A European J

View full text Add to dashboard Cite

The pincer-like double ester naphthalene-2,3-diyl-bis(4-fluorobenzoate) (2) is pentamorphic. Upon heating crystals of form I to below their melting point (441-443 K), they undergo a phase transition accompanied by a thermosalient effect, that is, rare and visually striking motility whereby the crystals jump or disintegrate. The phase transition and the thermosalient effect are reversible. Analysis of the crystal structure revealed that form I is a class II thermosalient solid. Crystals of form III also underwent a reversible phase transition in the temperature range of 160 to 170 K; however, they were not thermosalient. Comparison of the structures and the mechanical responses of the two polymorphs revealed that the thermosalient effect of form I was due to reversible closing and opening of the arms of the diester molecules in a tweezer-like action.

show abstract

“…1) by Mittapalli et al, reported in this issue of IUCrJ, revealed four polymorphs, three of which exhibit mechanical responses such as jumping (forms I and III) and exploding (form II) during phase transition at high temperature (Mittapalli et al, 2017). This is a rare example of a combination of mechanophysical responses in polymorphs of the same compound (Steiner et al, 1993;Crawford et al, 2007;Sahoo et al, 2013).…”

mentioning

confidence: 99%

Regulating thermosalient behaviour in three polymorphs

Werny

Vittal

2017

Int Union Crystallogr J

View full text Add to dashboard Cite

Dynamic molecular crystals can be defined as crystalline materials that respond to external stimuli with mechanical responses on a macro-, micro-or nanoscopic scale (Naumov et al., 2015). The motility of dynamic crystals is usually triggered by a phase transition or chemical reaction without gaseous products, subsequently creating local stresses in the densely packed crystal lattice of the respective material (Commins et al., 2016). The amplification of such strain via cooperative processes can lead to reversible or irreversible phase deformation, instantaneous propulsion and even disintegration. Crystalline materials, which are classically defined as rigid and brittle entities, thus display a reversible mechanical response in the form of shape change (curling, bending, twisting) or locomotion (jumping, flipping, rotation, etc.) (Nath et al., 2014). A class of dynamic single crystals, known as thermosalient crystals, can propel themselves over distances hundreds of times larger than their own size when they are exposed to heat. The earliest known thermosalient crystal, (phenylazophenyl)palladium hexafluoroacetylacetone, was reported more than 30 years ago (Etter & Siedle, 1983). Only in recent years, however, have researchers begun to fully investigate thermosalient phase transitions on a structural, kinematic and mechanistic basis. The observed conversion of heat energy into mechanical motion by a densely packed crystal lattice represents a phenomenon that could be integrated into a host of new applications, e.g. actuators, sensors and pressure-sensitive applications (Commins et al., 2016). In general, a limited yet distinct anisotropic expansion of the crystal unit cell is accompanied by the nucleation and propagation of a new phase within the bulk crystal (phase transition) (Nath et al., 2014). The resulting build-up of strain at the phase interface, if larger than the cohesive interactions present within the crystal lattice, instigates a mechanical force (self-actuation). Phenomena such as molecular dimerization, intermolecular charge transfer and intermolecular proton transfer depend on the way the molecules are assembled in a crystal. Similarly, the dynamic properties of crystals, which occur in response to external stimuli, are also controlled by the intermolecular interactions. Theinteractions, hydrogen bonds, halogen bonds and coordination bonds contribute decisively to the cooperative behaviour of the dynamic switching process. In the case of thermoresponsive materials, the dissipation of thermal energy is influenced by the crystal packing (Naumov et al., 2015). The study of a dichloro derivative of N-salicylideneaniline (see Fig. 1) by Mittapalli et al., reported in this issue of IUCrJ, revealed four polymorphs, three of which exhibit mechanical responses such as jumping (forms I and III) and exploding (form II) during phase transition at high temperature (Mittapalli et al., 2017). This is a rare example of a combination of mechanophysical responses in polymorphs of the same compound (Steiner et al., 1...

show abstract

Mechanochemical synthesis ofN-salicylideneaniline: thermosalient effect of polymorphic crystals

Cited by 34 publications

References 44 publications

Global Performance Indices for Dynamic Crystals as Organic Thermal Actuators

Global Performance Indices for Dynamic Crystals as Organic Thermal Actuators

Effect of Crystal Packing on the Thermosalient Effect of the Pincer‐Type Diester Naphthalene‐2,3‐diyl‐bis(4‐fluorobenzoate): A New Class II Thermosalient Solid

Regulating thermosalient behaviour in three polymorphs

Contact Info

Product

Resources

About