You missed us!
Here are some abstracts of talks that we have given.

Hybrid Approaches to Nanolithography and Chemical Patterning
C. Srinivasan, M. W. Horn, P. S. Weiss
Departments of Chemistry, Physics, and Engineering Science & Mechanics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Despite the impressive pace of innovations in photolithography, this technology faces fundamental physical and economic limitations for patterning sub-30-nm features.  We have combined photolithography, a top-down approach, synergistically with bottom-up chemical self-assembly to fabricate nanometer-scale features in a low-cost, scalable process - molecular-ruler nanolithography.^1,2  Here, we describe the strategies that have been developed to integrate this technique with CMOS-compatible materials and processes,³ patterns registered nanometer-scale features on quartz for use as the mold in nanoimprint lithography,⁴ with double the spatial frequency of features created by conventional lithographic techniques.⁵  We also use this methodology to fabricate connected device structures for ultranarrow channel length organic thin-film transistors and aligned metallic and semiconducting nanowires.

One of the limitations of photolithography is its inability to pattern chemical functionality on surfaces; chemically functionalized surfaces have applications ranging from biospecific recognition to molecular electronics.⁶  To address this issue, we developed lithography-assisted chemical patterning.  This technique utilizes a robust lithographic resist (LOR) that is capable of withstanding self-assembly deposition conditions to create high-quality chemical patterns.  The ability to pattern chemical functionalities without intercalation and with registered, parallel processing are some of its unique advantages.^7,8

1. A. Hatzor and P. S. Weiss, Science 2001, 291, 1019.
2. M. E. Anderson, L. P. Tan, M. Mihok, H. Tanaka, M. W. Horn, G. S. McCarty, P. S. Weiss, Adv. Mater. 2006, 18, 1020.
3. C. Srinivasan, M. E. Anderson, E. M. Carter, J. N. Hohman, S. S. N. Bharathwaja, S. Trolier-Mckinstry, P. S. Weiss, M. W. Horn, J. Vac. Sci. Technol. B 2006, 24, 3200.
4. C. Srinivasan, J. N. Hohman, M. E. Anderson, P. S. Weiss, M. W. Horn (submitted for publication).
5. C. Srinivasan, J. N. Hohman, M. E. Anderson, P. Zhang, P. S. Weiss, M. W. Horn, Proc. SPIE 2007, 6517, 65171I.
6. Y. Xia and G. M. Whitesides, Angew. Chem., Int. Ed. 1998, 37, 551.
7. M. E. Anderson, C. Srinivasan, J. N. Hohman, E. M. Carter, M. W. Horn, P. S. Weiss, Adv. Mater. 2006, 18, 3258.
8. C. Srinivasan, T. J. Mullen, J. N. Hohman, M. E. Anderson, A. A. Dameron, A. M. Andrews, E. C. Dickey, M. W. Horn, P. S. Weiss, ACS Nano 2007, 1, 191.

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
P. S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Precision Nanoscale Assemblies: Self-Assembled Monolayers, Clusters, and Nanoparticles
Rachel Smith, Materials Science Division, Lawrence Berkeley Laboratory, Berkeley, CA 94720, USA; Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA; WPI Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 Japan

Extracting Quantitative Single-Molecule Dynamics from Scanning Probe Images
Patrick Han, Adam R. Kurland, Brent A. Mantooth, Amanda M. Moore, E. Charles H. Sykes, Vin H. Crespi and Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We measure these interactions and the electronic perturbations that underly them using scanning tunneling microscopy. In these and other measurements, we collect substantial data sets in order to generate distributions with the statistics of ensemble-averaging techniques, while still retaining all the single molecule and environmental information. This requires new automated tools for acquisition and analyses. We also use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements.

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Patterning and Measuring Molecules Inserted into Controlled Self-Assembled Monolayer Matrices
P. S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We have devloped soft and hybrid lithographic strategies to pattern inserted single molecules. We use these surfaces to test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. We also use this control at the single-molecule level to prepare isolated small-molecule probes in well-defined chemical environments for biospecific capture for complex mixtures.

Saturday 8 March 2008
Pacific University Chemistry Symposium Honoring University Distinguished Professor James O. Currie, Jr.,
Pacific University, Forest Grove, Oregon

Imaging Single Molecule Polarizability and Buried Interface Dynamics
A. M. Moore, Y. Yao, J. M. Tour and P. S. Weiss
Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA
Department of Chemistry and Center for Nanoscale Science and Technology, Rice University

We have studied oligo(phenylene-ethylene) (OPE) molecules as candidates for molecular electronic switches. We previously determined the switching mechanism to rely on hybridization changes between the substrate and molecule. Here, we have determined which molecules will be more or less active in our samples using a custom-built alternating current scanning tunneling microscope (ACSTM). The polarizabilities of the OPE and host molecules are observed using the ACSTM magnitude signal. The stability of the ACSTM magnitude correlates to the stability of the switches in our samples. From this, we can determine which molecules are more likely to exhibit motion and/or switching events and which molecules will remain stable in our images.

Probing Single-Molecule Electronics and Dynamics
Amanda M. Moore, Department of Chemistry, The Pennsylvania State University, University Park, PA 16802-6300, USA

We have studied oligo(phenylene-ethylene) (OPE) molecules as candidates for molecular electronic switches using molecular engineering, scanning tunneling microscopy and spectroscopy. These molecules were inserted into host alkanethiolate self-assembled monolayers for isolation and individual addressability. Many different hypotheses and theoretical predictions have been put forth to describe conductance switching. We have assessed each through varying the molecular design of our switches and have concluded that the only mechanism consistent with all the switching data is changes in hybridization at the molecule-substrate bond. Furthermore, we have determined which molecules will be more or less active in our samples using a custom-built tunable microwave-frequency alternating current scanning tunneling microscope. The polarizabilities of the OPE molecules were observed using the microwave difference frequency magnitude signal. The stability of the difference frequency magnitude correlates to the stability of the switches in our samples. From this, we can determine which molecules are more likely to exhibit motion and/or switching events and which molecules will remain stable in sequential images.

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
P. S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Exploring and Controlling the Atomic-Scale World
P. S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Selecting and Driving Nanoscale Assembly in Monolayer Films through Tailored Intermolecular Interactions
T. J. Mullen, C. Srinivasan, M. J. Shuster, S. E. Brunker, L. M. Dominak, J. N. Hohman, A. A. Dameron, M. W. Horn, C. D. Keating, A. M. Andrews, and P. S. Weiss, Departments of Chemistry, Engineering Science & Mechanics, Physics, and Veterinary & Biomedical Science, The Pennsylvania State University, University Park, PA 16802-6300, USA

Nanoscale Self- and Directed Assembly
T. J. Mullen, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We employ some of these approaches in directed assembly to enable bioselective and biospecific binding. We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We quantitatively compare the conductances of molecule-substrate junctions. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We employ some of these approaches in directed assembly to enable bioselective and biospecific binding. We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We quantitatively compare the conductances of molecule-substrate junctions. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

Introducing ACS Nano
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Biocapture Surfaces and Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics and Anne M. Andrews, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film.

We employ some of these approaches in directed assembly and chemical patterning to enable bioselective and biospecific binding. These probes are isolated in well-defined matrices and spaced at the sub-10-nanometer scale using combinations of soft lithography, conventional lithography, and self-assembly. We have developed the patterning tools, as well as the diagnostics and metrology tools for these new chemically patterned structures.

We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We employ some of these approaches in directed assembly to enable bioselective and biospecific binding. We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We quantitatively compare the conductances of molecule-substrate junctions. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

Creating and Probing Molecular Assemblies for Single-Molecule Devices
Amanda M. Moore, Department of Chemistry, The Pennsylvania State University, University Park, PA 16802-6300, USA

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We employ some of these approaches in directed assembly to enable bioselective and biospecific binding. We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We quantitatively compare the conductances of molecule-substrate junctions. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

How Can We Impact the Future with (New Materials,) New Methods and New Measurements?
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

Designing, Measuring and Controlling Molecular- and Supramolecular-Scale Properties for Molecular Devices
Paul S. Weiss, Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802-6300, USA

We use molecular design, tailored syntheses, intermolecular interactions and selective chemistry to direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measurements of single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood and exploited at unprecedented scales. We look at how these interactions influence the chemistry, dynamics, structure, electronic function and other properties. Such interactions can be used to advantage to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. These nanostructures can be taken all the way down to atomic-scale precision or can be used at larger scales. We select and tailor molecules to choose the intermolecular interaction strengths and the structures formed within the film. We employ some of these approaches in directed assembly to enable bioselective and biospecific binding. We also selectively test hypothesized mechanisms for electronic switching by varying molecular design, chemical environment, and measurement conditions to enable or to disable functions and control of these molecules with predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule measurements in order to develop sufficiently significant statistical distributions, comparable to those found in ensemble-averaging measurements, while retaining the heterogeneity of the measurements. We quantitatively compare the conductances of molecule-substrate junctions. We demonstrate the importance of these junctions in conductance switching of single molecules. We now apply these strategies to photo-driven, electrochemically-driven, and chemically-driven motion in single molecules and assemblies. This enables us to address how concerted nano-scale motions can be used to drive motion at larger scales. The atomic-scale details provide surprising and useful insights into the limitations and opportunities of cooperative motion.

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30 June 2008
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