The results of a variety of experiments used to characterize fullerenes, metallofullerenes and alkali-metal intercalated C60 are reported. It is shown that differential scanning calorimetry and NMR characterization of the orientational phase transition in C60 provide sensitive means to assess the purity and crystallinity of fullerene samples. The results of a mass-spectrometric investigation of metallofullerene samples produced by co-vaporization of carbon and metals are described. An account is given of some electron paramagnetic resonance results obtained for LaC82 and solid-state NMR results obtained on an alkali-intercalated fullerite, Rb3C60, which show for the first time the presence of magnetically inequivalent carbons in underivatized C60. Together these experiments yield a great deal of information about the phase purity, molecular dynamics and structure of a variety of fullerene materials.

A phase-shifting mask without chrome opaque features can be used to print groove servo patterns for optical storage disks and provides improved contrast and resolution in printed photoresist images when used in a projection printer such as a Perkin-Elmer MicralignTM-500 mask aligner. Such a phase-shifting photomask structure can be fabricated in the following way. Onto a conventional photoresist coated chrome on fused quartz photomask blank is written a pattern of concentric lines and spaces or a spiral pattern. The photoresist is developed and the exposed chrome etched in the conventional way to yield a transmission mask pattern of twice the pitch desired in the final groove pattern. The quartz is then etched, using the photoresist/chrome and/or chrome pattern as the resist, by either a wet or dry process, to a uniform depth. The chrome is then completely removed to form a ‘‘chromeless’’ phase-shifting mask [K. K. H. Toh, G. Dao, R. Singh, H. Gaw, Proc. SPIE 1991 Symp. Microlithogr. 1463 (1991)] Phase-shifting masks of this sort have been fabricated and used successfully to print photoresist images on glass disks yielding patterned photoresist structures of 1.5, 1.2, and 1.0 μm pitch. The resulting photoresist pattern could be transferred into the glass substrate by a wet etch process to generate the desired glass etch pattern after photoresist removal. Phase-shifting masks of this design require careful dimensional control in three dimensions. One modification to the phase mask design described which simplifies the fabrication process is to alter the relative dimensions of the groove and land. If the land is made very small in relation to the groove, then the groove prints as though it were a clear feature in a transmission mask. Conversely, the land prints as though it were a chrome (‘‘dark’’) feature. The contrast obtained in the image is much larger than can be obtained from a conventional transmission mask of similar dimensions and the depth of focus was increased to >10 μm. This ‘‘darker than dark’’ phase-shifting mask phenomenon may prove valuable in the fabrication of complex patterns [K. K. H. Toh, G. Dao, R. Singh, and H. Gaw, SPIE 1991 Symp. Microlithogr. 1463 (1991) and K. Nakagawa, M. Taguchi, and T. Ema, Fabrication of 64M DRAM with i-line Phase Shift Lithography, IEEE International Electron Devices Meeting, Dec. 9–12, 1990, San Francisco, California].

Certain optical data systems rely upon the ability of the laser to accurately track along grooves in the substrate. The topography and physical properties of the substrate, laser beam characteristics (wavelength, spot size), and physical optics of the optical head all play a role in determining whether tracking is possible on a given optical disk. The effects of each of these variables can be found by modelling the disk as a phase surface which modulates the phase of the incident laser light. Scalar diffraction thcory[l,2] can be used to predict the reflected light intensity as a function of position across the disk for a given system. It is then possible to predict the servo signals which are used for tracking. The primary substrate parameters which affect these tracking signals are the groove depth, the relative widths of the groove and land (duty cycle), the track pitch, the refractive index, and the groove topography. All of these disk properties, excluding the refractive index, are found using Scanning Tunneling Microscopy (STM)[3]. This gives a detailed three dimensional surface profile for the disk which is then used in the theoretical calculation of the tracking servo signals. These calculated values are compared to actual experimental data obtained using an optical disk tester. Disks were measured which have varying depth and varying track pitch at fixed depth.

Scanning tunneling microscopy (STM) was employed to measure the three-dimensional surface topography of radial servo grooves etched in a glass substrate. The effect of groove depth (nominal values of 20, 40, and 70 nm) on tracking servo signals at a track pitch of 1.6 μm is examined. Using an optical disk tester, three groove related signals were measured for each groove depth: the on-track signal ratio, cross-track ratio, and the push-pull ratio. In a key feature of this study, scalar diffraction theory was used to calculate the groove related signals from the STM profiles and the beam profile of the optical disk tester. The calculated groove related signals were found to be in nearly quantitative agreement with those measured with the disk tester.

L'etude par RMN 13 C et spectrometrie IR montre que, contrairement a des resultats recemment publies sur sa solubilite, le poly(acide 4-hydroxy benzoique) est degrade lors des essais de dissolution dans l'acide trifluoromethanesulfonique.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDirect evidence for transesterification and randomization in a mixture of homopolyesters of poly(4-hydroxybenzoic acid) and poly(6-hydroxy-2-naphthoic acid) above 450.degree.A. Muhlebach, James Economy, R. D. Johnson, T. Karis, and J. LyerlaCite this: Macromolecules 1990, 23, 6, 1803–1809Publication Date (Print):March 1, 1990Publication History Published online1 May 2002Published inissue 1 March 1990https://doi.org/10.1021/ma00208a041RIGHTS & PERMISSIONSArticle Views174Altmetric-Citations44LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (855 KB) Get e-Alerts Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDiad sequence distribution in copolyesters of 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acidA. Muhlebach, R. D. Johnson, J. Lyerla, and J. EconomyCite this: Macromolecules 1988, 21, 10, 3115–3117Publication Date (Print):October 1, 1988Publication History Published online1 May 2002Published inissue 1 October 1988https://pubs.acs.org/doi/10.1021/ma00188a035https://doi.org/10.1021/ma00188a035research-articleACS PublicationsRequest reuse permissionsArticle Views216Altmetric-Citations41LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

An p‐Xylol und γ‐Butyrolacton im Interlamellarraum des Schichtsilicats Hectorit wurde geprüft, welche Möglichkeiten die NMR‐Spektroskopie für die Untersuchung solcher Intercalationsverbindungen bietet. Mit einem gepulsten FT‐NMR‐Spektrometer kann die Bewegungsfreiheit eines eingeschobenen organischen Moleküls, die Zusammensetzung von Mischungen und sogar die Lage von Keto‐Enol‐Gleichgewichten bestimmt werden.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of internal motion on the carbon-13 relaxation times of methyl carbonsJames R. Lyerla Jr. and David M. GrantCite this: J. Phys. Chem. 1972, 76, 22, 3213–3216Publication Date (Print):October 1, 1972Publication History Published online1 May 2002Published inissue 1 October 1972https://pubs.acs.org/doi/10.1021/j100666a019https://doi.org/10.1021/j100666a019research-articleACS PublicationsRequest reuse permissionsArticle Views52Altmetric-Citations35LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTField-dependent contributions to carbon-13 nuclear relaxationJames R. Lyerla Jr., David M. Grant, and Richard D. BertrandCite this: J. Phys. Chem. 1971, 75, 26, 3967–3971Publication Date (Print):December 1, 1971Publication History Published online1 May 2002Published inissue 1 December 1971https://doi.org/10.1021/j100695a009RIGHTS & PERMISSIONSArticle Views69Altmetric-Citations65LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (566 KB) Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDipolar contributions to carbon-13 relaxation timesDavid M. Grant, James R. Lyerla Jr., and Robin K. HarrisCite this: J. Phys. Chem. 1971, 75, 4, 585–588Publication Date (Print):February 1, 1971Publication History Published online1 May 2002Published inissue 1 February 1971https://pubs.acs.org/doi/10.1021/j100674a025https://doi.org/10.1021/j100674a025research-articleACS PublicationsRequest reuse permissionsArticle Views42Altmetric-Citations15LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation James R. Lyerla, David M. Grant, C. H. Wang; Carbon‐13 Spin—Rotational Relaxation in CH3I and CH3CN. J. Chem. Phys. 1 November 1971; 55 (9): 4676–4677. https://doi.org/10.1063/1.1676821 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioThe Journal of Chemical Physics Search Advanced Search |Citation Search

ADVERTISEMENT RETURN TO ISSUEPREVArticleEffect of molecular association on carbon-hydrogen nuclear dipolar relaxation ratesTerry D. Alger, David M. Grant, and James R. Lyerla Jr.Cite this: J. Phys. Chem. 1971, 75, 16, 2539–2540Publication Date (Print):August 1, 1971Publication History Published online1 May 2002Published inissue 1 August 1971https://pubs.acs.org/doi/10.1021/j100685a026https://doi.org/10.1021/j100685a026research-articleACS PublicationsRequest reuse permissionsArticle Views45Altmetric-Citations21LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts