Organic electronics have made significant progress, thanks to the precise understanding of efficient organic semiconducting materials’ design and synthesis. In a recent study, researchers John, George, and Hariharan have highlighted the significance of crystalline packing morphologies adopted by organic chromophores for effective charge transport properties from a crystal engineering perspective. The study provides different strategies adopted to modulate the crystalline packaging in organic scaffolds for efficient charge transport properties.
Outcomes:
- The study explores the correlation between diverse crystalline packing morphologies adopted by organic chromophores and charge transport properties from a crystal engineering perspective.
- The synthetic versatility of organic molecules allows for a wide range of design approaches to be used in organic electronics.
- Different strategies, including polymorphism, cocrystallization, noncovalent interactions, heteroatom functionalization, orientation of the molecule, and shape of the molecule, can be employed to modulate the packing in organic crystals, thereby altering the charge transport properties of the system.
- The researchers highlight the significance of nonequal ratio cocrystal engineering to achieve packing structures conducive for charge transport.
- The study shows that small variations in the molecular packing can result in considerable changes in charge carrier mobilities.
- The research sets the groundwork for more organic compounds with cross-architecture in the solid-state to build a library of molecules with selective charge transport.
- The study emphasizes the importance of deciphering charge carrier dynamics in crystalline organic materials for further development in organic electronics.
The emergent electronic properties of chromophoric systems in the crystalline state are determined by the molecular structure and the noncovalent interactions between the neighboring molecules in the solid-state. The study highlights the different strategies used to experimentally measure the charge carrier mobility, including time-of-flight (TOF) technique, field-effect transistor (FET) configuration, Hall effect mobility, space charge-limited current techniques, the method of charge extraction by linearly increasing voltage, and time-resolved microwave conductivity measurements.
Theoretical and experimental assays on peri-substituted pentacenes are further validated by P2’s substantial hole and electron mobility compared to P1’s significant hole effective mass revealed by DFT calculations. The researchers construct IC2-DPAO and ICFO with 2:1 and 1:1 ratios using a model compound indolo[2,3-a]carbazole (IC), and 9-fluorenone (FO) and 2,6-diphenylanthraquinone (DPAO) coformers, respectively, highlighting the significance of nonequal ratio cocrystal engineering to achieve packing structures conducive for charge transport.
Small variations in the molecular packing can result in considerable changes in charge carrier mobilities, because of which modulating the shape of the molecule is emerging as a cutting-edge design method for tweaking charge transport. The study also emphasizes the relevance of aromaticity in stabilizing crystal packing favoring charge transport, which is an area that is still evolving and needs more inspection.
Despite the multiple methods described in this Perspective to tune crystal packing for efficient charge transport, a variety of approaches still need to be explored and comprehended. Hence deciphering charge carrier dynamics in crystalline organic materials is a key theme for further development in organic electronics. The researchers believe that the study sets the groundwork for more organic compounds with cross-architecture in the solid-state to build a library of molecules with selective charge transport, which will be vital for future advancements in organic electronics.
Charge Transport through Discrete Crystalline Architectures
John; George; Hariharan
Full-text link: https://doi.org/10.1021/acs.jpcc.2c08837
What this paper is about
- The drastic progress in the field of organic electronics can be attributed to the precise understanding of the design and synthesis of efficient organic semiconducting materials.
- Charge transport at the molecular level is significantly influenced by the intermolecular electronic coupling and the molecular reorganization energy.
- Exploring the correlation between diverse crystalline packing morphologies adopted by organic chromophores and charge transport properties from a crystal engineering perspective is a significant area of research for the design of advanced functional materials.
What you can learn
- The synthetic versatility of organic molecules allows a wide range of design approaches to be used in organic electronics.
- The emergent electronic properties of chromophoric systems in the crystalline state are dictated by the molecular structure and the noncovalent interactions between the neighboring molecules in the solid state.
- Different strategies including polymorphism, cocrystallization, noncovalent interactions, heteroatom functionalization, orientation of the molecule, and shape of the molecule can be employed to modulate the packing in organic crystals, thereby altering the charge transport properties of the system.
Core Q&A related to this research
- What is the focus of the paper “Charge Transport through Discrete Crystalline Architectures”?
- The paper focuses on exploring the correlation between diverse crystalline packing morphologies adopted by organic chromophores and charge transport properties from a crystal engineering perspective.
- What can we learn about the synthetic versatility of organic molecules from this paper?
- The synthetic versatility of organic molecules allows a wide range of design approaches to be used in organic electronics.
- How do noncovalent interactions impact the emergent electronic properties of chromophoric systems in the crystalline state?
- The emergent electronic properties of chromophoric systems in the crystalline state are dictated by the molecular structure and the noncovalent interactions between the neighboring molecules in the solid state.
- What are some of the strategies employed to modulate the packing in organic crystals and alter the charge transport properties of the system?
- Different strategies including polymorphism, cocrystallization, noncovalent interactions, heteroatom functionalization, orientation of the molecule, and shape of the molecule can be employed to modulate the packing in organic crystals, thereby altering the charge transport properties of the system.
- What experimental techniques are used to measure charge carrier mobility in organic materials?
- Experimental techniques used to measure charge carrier mobility in organic materials include time-of-flight (TOF) technique, field-effect transistor (FET) configuration, Hall effect mobility, space charge limited current techniques, method of charge extraction by linearly increasing voltage, and time-resolved microwave conductivity measurements.
- How do small variations in the molecular packing impact charge carrier mobilities?
- Small variations in the molecular packing can result in considerable changes in charge carrier mobilities.
- Why is deciphering charge carrier dynamics in crystalline organic materials a key theme for further development in organic electronics?
- Deciphering charge carrier dynamics in crystalline organic materials is a key theme for further development in organic electronics because it can lead to the design of advanced functional materials with efficient charge transport properties.
Basics Q&A related to this research
Polymorphism
A: Polymorphism refers to the phenomenon where a substance can exist in different crystal structures or packing arrangements while maintaining the same chemical composition.
Cocrystallization
A: Cocrystallization is a process in which two or more different molecules are crystallized together to form a new material that exhibits properties different from the individual components.
Heteroatom functionalization
A: Heteroatom functionalization is the process of introducing atoms other than carbon and hydrogen into a molecule to modify its electronic and chemical properties.
Orientation
A: Orientation refers to the relative arrangement or alignment of the molecules in a material. It can affect the physical and chemical properties of the material.
Shape of the molecule
A: The shape of a molecule can have a significant impact on the physical and chemical properties of a material. It can affect molecular packing, intermolecular interactions, and charge transport properties, among other factors.
Charge carrier mobility
A: Charge carrier mobility refers to the ability of charges (electrons or holes) to move through a material in response to an electric field. It is an important property in many electronic and optoelectronic applications.
Time-of-flight
A: Time-of-flight is a measurement technique used to determine the speed and mobility of charge carriers in a material by measuring the time it takes for them to travel a certain distance.
Field-effect transistor
Q: What is a field-effect transistor in materials science? A: A field-effect transistor is an electronic device that can amplify or switch electronic signals by controlling the flow of charges through a semiconductor material via an external electric field.
Hall effect mobility
A: Hall effect mobility is a measure of charge carrier mobility that is determined by the voltage induced in a semiconductor material by an external magnetic field.
Space charge limited current
A: Space charge limited current refers to the phenomenon where the flow of charge carriers in a material is limited by the accumulation of charges at the interfaces or surfaces.
Charge extraction by linearly increasing voltage
A: Charge extraction by linearly increasing voltage is a technique used to measure the mobility and recombination dynamics of charges in a material by applying a linearly increasing voltage pulse.
Microwave conductivity measurements
A: Microwave conductivity measurements are a non-destructive technique used to determine the electrical properties of materials, particularly the conductivity and dielectric constant, using microwaves.
π-Conjugated materials
A: π-Conjugated materials are organic or inorganic compounds that have a delocalized π-electron system, which enables them to exhibit unique electronic, optical, and magnetic properties.
Nonlinear aromatic core
A: A nonlinear aromatic core is a type of π-conjugated system that has a nonlinear structure due to the incorporation of different types of rings or atoms, which gives it unique electronic and optical properties.
Polymorphs
A: Polymorphs are different crystal structures or packing arrangements that can exist for the same chemical compound.
