Langmuir focuses on interfaces that govern the properties and performance of materials and systems. While in recent years the emphasis has been more strongly placed on fundamental studies, Langmuir is expanding its scope to welcome reports of applications that result from the rational design of interfaces. We are looking especially for manuscripts that report innovative interface design concepts. In addition, we seek reports of the novel expression of such concepts in applications in emerging areas that are attractive to both scientists and engineers. Papers that make a clear connection between fundamental work and applications will provide value to researchers in materials science and device creation across the broad gamut of interface science, and such papers are sure to be impactful contributions to the field that will be well read and cited. That being said, Langmuir has a prominent place at the center of interface science, and for example, Langmuir articles described ground-breaking colloid science long before nanoparticles were specified.(1) As we embark upon publication of the 36th volume of Langmuir, it is important to acknowledge that history but to also look forward and position the journal as the home for future advancements in the field. We aim for its recognition as the “go-to” platform via which to report new and emerging directions in interface science from their very beginning. I’d like to emphasize that many of the topical areas previously published in the journal will go unchanged. I, therefore, ensure long-time authors, reviewers, and readers, without whom the journal would not have attained its success, that we continue to welcome this core journal community. It is worth providing some detail about how the scope of the journal is changing, which I summarize next. Prof. Gilbert C. Walker, Distinguished Professor, Department of Chemistry, University of Toronto; Associate Scientific Director, Nanomedicines Innovation Network; and incoming Editor-in-Chief of Langmuir The journal has an embracing interest in studies of surfaces and interfaces (synthetic and natural), including adsorption, surfactants, emulsions, ultrathin films, forces, and dynamics. New surface chemistry will be key to many articles. The journal seeks reports of solutions to important unsolved problems in interface-driven stability: response, organization, and self-organization of (nano)particle suspensions and structures. The journal’s scope will expand its coverage of exceptional results in rheology, mechanics, and nonequilibrium thermodynamics. Understanding charge regulation, transfer at interfaces, and electrochemistry is remarkably underdeveloped, especially for material interfaces composed of macromolecules. I believe that high-quality quantitative studies using both model and practically useful materials will advance the field. These are essential for developing interfacial processes for energy storage and transduction and catalysis (including that in metal–organic frameworks). The journal’s scope will be expanded to highlight 2D van der Waals materials, including polar dielectrics whose surface properties are open frontiers of conductance, mechanics, photonics, and catalysis. Confinement is also key to the behavior of single molecules and particles at interfaces, and the journal seeks breakthrough studies of the connection between physical confinement and reaction paths. Finally, the journal’s scope in biointerfaces will expand. While Langmuir has long reported excellent studies of synthetic surfaces in vivo and in vitro, breakthroughs are needed, especially to achieve the goal of therapeutic-quality, specific targeting of nanoparticles to chosen organs. To make scientific life even more interesting, in most of the work described above, understanding and controlling dynamics at interfaces will be essential. The field of interface science and engineering needs new methods for imaging dynamics, and Langmuir aims to foster these needed advances. The broadening of the scope will reaffirm Langmuir’s unique position in disseminating new knowledge and will attract a wider audience. As a practical matter related to the expansion of journal scope, you may notice some changes to both the manuscript submission process at Langmuir and the way in which articles are organized within each issue. Langmuir has been organizing articles within each issue under seven topic headings, and authors have been asked to choose which heading is most appropriate for their paper from a dropdown menu during manuscript submission. To reflect the broadening of scope and ever-evolving nature of interface science, we are removing these topical sections from the journal. For authors who are submitting manuscripts as of January 2020, you will notice that this question has been removed from the submission process. For manuscripts submitted prior to 2020 but not yet published, you will notice that though you selected a journal topical section during manuscript submission, the articles in the issue are no longer grouped under sections. We hope you find the manuscript process to be more streamlined and you feel your research is welcomed by the journal, independent of these past topical headings. Langmuir aims to add more fun. This comes naturally, I believe, by the journal conversing with its readers through special/virtual issues and, again, editorials. These instruments create community, excitement, and perspectives on where the field is going. Perhaps more importantly they can speculate about what else can be done in a field. These are “big picture” articles that will guide graduate students as they think about what field to choose, early-stage independent researchers who are trying to organize their laboratories, and experienced scientists who cannot resist gossip! Chemistry of Materials has an interesting platform for young scholars called Up & Coming Perspectives (https://connect.acspubs.org/CM-UC-Perspectives?utm_source=CMFC&utm_medium=LP&utm_campaign=UCP) aimed at providing a forum for early career scientists. This has become a hot new opportunity for these scholars to show off their work. An editorial goal, which I share, is to develop a mechanism where young researchers see there will be value in commitment to a journal. We want our authors to report on emerging fields. I look forward to working with our early career advisory board to develop these opportunities, and I welcome suggestions. I have worked in the field of interfacial science and engineering for over 25 years. My interests are diverse and began with studies of ultrafast solvation and its coupling to electron transfer. More recently I have been interested in the quantitative understanding of water’s role in the self-assembly of amphiphiles. My group has developed imaging techniques that measure multiple interfacial properties simultaneously; examples include nanophotonic, -mechanical, -electrical, and -magnetic responses, especially in block copolymer thin films, their composites, and other dielectric interfaces. These nanoscale studies have helped us to understand, for example, how amphiphilic polymers interact with living cells at hierarchical length scales. I try to translate our results when it is practical. Recently, we have been collaborating in the development of nanoscale delivery vehicles for medicines. The team of Senior Editors and the Editorial Advisory Board for Langmuir is superb, with deep expertise and passion for advancing the field. We are lucky to have wide representation of geographic, topical, and gender diversity, and we plan to expand it even further. In closing, I’d like to thank Professor Françoise Winnik for her committed effort as Editor-in-Chief over the past 5 years. Her professionalism, spirit of fairness, and great enthusiasm for interface science has been inspiring. Views expressed in this editorial are those of the author and not necessarily the views of the ACS. This article references 1 other publications. This article has not yet been cited by other publications. This article references 1 other publications.

Getting to know the authors, reviewers, and readers from a broad range of institutions located around the world and at different stages in their career is one of the most exciting aspects of working with Langmuir. This global community is united in accumulating new knowledge on various facets of science where the interface plays an important role. In this virtual issue, we are delighted to highlight the invaluable contributions of authors from India whose publications form a set of the most widely read and highly cited articles over the last 3 years. We consider these Langmuir publications to be a sample collection of the recent exciting work on soft materials and interfaces authored by Indian scientists. Mindful of the various limitations, we have tried our best to select a cross section of authors spread throughout India. This collection includes articles from first timers as well as those who have published with Langmuir for several years. The representative authors with science and engineering backgrounds come from a wide spectrum of national laboratories, research and academic institutes, and universities located in various parts of India. The selection spans articles from a broad range of interface science with an emphasis on materials and organized self-assemblies in general. Selected papers include invited feature articles as well as regular articles. The former summarizes the authors’ contributions during the last several years to a given topic, while the latter reports the findings for the first time. The selection includes articles that focus on materials for energy and catalysis; materials with tunable photonic and electronic properties; materials at the interface with biological systems; and soft materials and self-assembly where the interface dominates. Khushalani (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b02953), Bhattacharyya (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b00293), Chandrasekaran (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.6b02413), and Basu and Pande (https://pubs.acs.org/doi/10.1021/acs.langmuir.7b00029) present their findings on new methods to harness energy. Since the time of J. C. Ghosh and C. V. Raman, the exploration of the photonic and electronic properties of molecules and materials has interested Indian scientists. The search for soft matter and hard nanomaterials with unique electronic and photonic properties continues. Articles by Sudhakar (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b01081), Das (https://pubs.acs.org/doi/10.1021/acs.langmuir.7b00452), Mukhopadhyay (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b02352), Pal (https://pubs.acs.org/doi/10.1021/acs.langmuir.6b04100), and Ghosh (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b00926) are a few representative publications on this topic during the last 3 years. Langmuir is keen on spotlighting articles that highlight the fundamental and applied aspects of soft materials. Diverse assemblies such as liquid crystals, amphiphiles, colloids, clays, emulsions, and gels covered in articles by Pal (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b03031), Hassan (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b02921), Basavaraj (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b01139), Joshi (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b01830), Mandal (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b03364), and Ghosh (https://pubs.acs.org/doi/10.1021/acs.langmuir.6b03192) provide a glimpse of activities in India on this important topic of soft materials. Such soft materials have made inroads in recent times into biomedical fields. Employing state-of-the-art techniques, Maiti (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.8b02147), Pandey (https://pubs.acs.org/doi/10.1021/acs.langmuir.7b03152), Ghosh (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b01713), Sen (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b02291), and Jana’s (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b00376) articles bring out the value of biomaterials, nanomaterials, and soft materials in varied applications such as drug delivery, antibacterial activity, cell adhesion, and cellular and subcellular penetration. Langmuir, the premier journal in which early results on nanoparticles were disclosed, continues to be a popular home for such work. Since the discovery of gold nanoparticles, the search for “nano” has extended to metallic and bimetallic clusters, aggregates of polymers, and organic molecules. The invited feature articles by Prasad (https://pubs.acs.org/doi/10.1021/acs.langmuir.7b00193) and Pradeep (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b03493) outline the mechanism of metallic nanoparticle formation and their use as catalysts. Along these lines, Sarkar (https://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b01072) summarizes his recent findings of the aggregation of a cancer drug. The value of nanocrystals in energy research has been brought out in the articles by Bhattacharyya (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b00293) and Basu and Pande (https://pubs.acs.org/doi/10.1021/acs.langmuir.7b00029). To cap and end the collection of these diverse topics, the final articles emphasize the role of the interface in fundamental and applied research by Hassan (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b02921) and Toley (https://pubs.acs.org/doi/10.1021/acs.langmuir.8b01345). Overall, it is clear from this small collection that both application-oriented, and fundamental research related to “interfaces” and “soft materials” is vibrant in India, and Langmuir continues to be an attractive journal to these researchers. We look forward to working together with all researchers from India in making available their pioneering results to the world community. We hope you will enjoy this collection of articles from authors in India and look forward to your participation as we highlight the contributions of Langmuir authors to interface science from around the globe! Views expressed in this editorial are those of the authors and not necessarily the views of the ACS. This article has not yet been cited by other publications.

Tadmor et al.’s 2009 PRL article shows experiments of pendant drops with ∼30% higher retention forces than their sessile analogues. A recent article (de la Madrid, R. et al. Langmuir2019, 35, 2871) seemingly explains this result theoretically using a drastically different experimental system that shows a ∼3% higher force that exceeds the scatter in three out of four data points. The differences between the two experimental systems might have allowed the two theories to coexist, but Tadmor’s theory, which can explain both, allows an understanding of the solid–liquid interaction, which the newer theory lacks.

We address the issues raised in the Tadmor article (Tadmor, T., et al. Comment on “Comparison of the Lateral Retention Forces on Sessile, Pendant, and Inverted Sessile Drops”. Langmuir2019, 10.1021/acs.langmuir.9b02660). In particular, we explain why we did not use Tadmor’s theory to explain our results.