Comprehensive overview of molecular aggregates in different fields

Molecular Design of Opto-Electronic Materials: From Single Molecules to Molecular Aggregates delivers insights on molecular packing and its practical applications, from basic knowledge of organic compounds as a single molecule to the aggregated state. The book reviews aspects of molecular packing including internal mechanisms, main effective factors, control methods, and preferred structures in various functional materials.

Molecular Design of Opto-Electronic Materials includes information on:

• Research methodology of molecular aggregation science, covering theoretical calculations, general methods, and other methods
• Photoluminescence of molecular aggregates, covering fluorescence, thermally activated delayed fluorescence (TADF), and phosphorescence
• Molecular aggregates as active layers in organic solar cells, covering effects of donor and acceptor aggregates
• Molecular aggregates for second-order nonlinear optical effect, covering microscopic and macroscopic nonlinearities of organic systems, and organic molecules and polymers for second-order nonlinear optics
• Other opto-electric materials in aggregate, including magnetic and radical materials as well as metal- and covalent-organic frameworks

Molecular Design of Opto-Electronic Materials is an excellent reference for chemists, materials scientists, physicists, and electrical engineers involved in development of opto-electronic materials who are seeking to expand their knowledge bases and stay up-to-date with current applications.

Preface xi

1 A Brief Introduction to Molecular Aggregates 1
Jiaqiang Wang, Juqing Gu, Guigui Ye, Wei Cao, Meng Wang, Changzun Jiang, Shuhui li, Arui Huang, Qianqian li, and Zhen li

1.1 Introduction 1

1.1.1 Motivation 1

1.1.2 A Brief History 4

1.1.3 Basic Knowledge of Organic Compounds in Aggregated States 7

1.1.3.1 The Driving Force of Molecular Aggregates 7

1.1.3.2 The Adjustment of Molecular Interactions in Molecular Aggregates 10

1.1.4 Overview of Topics Covered 13

References 17

2 The Molecular Engineering and Fabrication Processes for Molecular Aggregates 33
Yujie Yang, Boxi Wu, Wentao Yuan, Shiyue Tang, Panpan Qiao, Yifan Niu, Peidong Xie, Ruixing Wang, Yan Gao, Yuexin Li, Wanni Yao, Kai Wang, Qianqian li, and Zhen li

2.1 Crystal Engineering 33

2.1.1 Organic Crystals Grown from Solution 34

2.1.1.1 Solvent Evaporation Method 34

2.1.1.2 Slow Cooling Method 36

2.1.1.3 Vapor Diffusion Method 36

2.1.1.4 Liquid-Liquid Diffusion Method 37

2.1.2 Vapor Phase Growth Method 37

2.1.3 Melt Growth 37

2.1.3.1 Bridgman-Stockbarger Method 38

2.1.3.2 Subcooled Melt Method 38

2.1.3.3 Zone-melting Recrystallization 39

2.1.3.4 Czochralski Growth Method 40

2.1.3.5 Laser Heating Base Method 40

2.2 Self-assembly System 41

2.2.1 Drivers of Molecular Self-assembly 41

2.2.1.1 Hydrogen Bonding Interactions 41

2.2.1.2 Hydrophobic Effect 42

2.2.1.3 Electrostatic Interactions 43

2.2.1.4 pi-pi Interaction 43

2.2.1.5 Coordination Interactions 43

2.2.2 Aggregation Types in Molecular Self-assembly 44

2.2.2.1 Nanoparticles 44

2.2.2.2 Membranes 44

2.2.2.3 Micelles 45

2.2.3 Control Methods of Molecular Self-assembly 45

2.2.3.1 Stimuli-responsive Self-assembly 46

2.2.3.2 Solvent Evaporation Self-assembly 46

2.2.3.3 Template-guided Self-assembly 48

2.2.3.4 Adsorption-based Self-assembly 48

2.3 Gel System 49

2.3.1 Chemical Gels 50

2.3.1.1 Free Radical Polymerization 50

2.3.1.2 Dynamic Covalent Cross-linking 51

2.3.1.3 Radiation Cross-linking 52

2.3.2 Supramolecular Gels 53

2.3.2.1 Electrostatic Interactions 53

2.3.2.2 Hydrophobic Interactions 54

2.3.2.3 Crystallization 55

2.3.2.4 Hydrogen Bonding 55

2.3.2.5 Ligand Binding 56

2.3.2.6 Host-Guest Interaction 58

2.4 Cross-linking System 59

2.4.1 Chemical Cross-linking 59

2.4.1.1 Triggered by Chemical Agents 59

2.4.1.2 Triggered by Heat 60

2.4.1.3 Triggered by Light 61

2.4.1.4 Triggered by Radicals 61

2.4.2 Physical Cross-linking 62

2.4.2.1 Physical Entanglement 63

2.4.2.2 Hydrogen Bonding 63

2.4.2.3 Crystallization 63

2.4.2.4 Ionic Interactions 63

2.4.2.5 Self-assembly and Supramolecular Interactions 63

2.4.3 Radiation Cross-linking 63

2.4.4 The Advantages of Cross-linking in the Regulation of Aggregated Structures 64

2.4.4.1 Fixed Orientation and Structural Stability 64

2.4.4.2 Enhanced Mechanical Properties 65

2.4.4.3 Dynamic Covalent Bonding for Adaptive Materials 66

2.5 Host-Guest System 67

2.5.1 Non-covalent Interactions in the Host-Guest System 68

2.5.1.1 Hydrogen Bonding 68

2.5.1.2 Hydrophobic Interactions 69

2.5.1.3 Electrostatic Interactions 69

2.5.1.4 pi-pi Interactions 70

2.6 Conclusion 70

References 70

3 The Research Methodology of Molecular Aggregation Science 87
Jiajia Song, Aisen li, Kun Yang, Weilong Che, and Zhen li

3.1 The Theoretical Calculation 87

3.1.1 Introduction 87

3.1.2 Overview of Quantum Chemistry Calculation 88

3.1.2.1 Ab Initio Calculation 89

3.1.2.2 Density