Top of Page
CLICK on the image to display webpage of aravamudhan: http://www.ugc-inno-nehu.com/
DR.S.ARAVAMUDHAN
http://www.ugc-inno-nehu.com/
Click on image for a website of Aravamudhan

   BIODATA                    CONTACT INFO
   Curriculum Vitae/Resume     webpages_list
   http://nehuacin.tripod.com

Phone Mobile: +919862053872
EMAIL:- inboxnehu_sa@yahoo.com
                saravamudhan@hotmail.com
                aram1121944@gmail.com
Please download Java(tm).
For best view,display with:
zoom="100%"  :  text size="smallest"

Symposia: 2009 & 2010
CLICK HERE to display webpage for symposia in Jan.-Mar. 2011


Last update by Aravamudhan at Shillong, on Monday, May 10, 2010

Participation in the  96th Indian Science Congress  at NEHU, Shillong from 3-7, January 2009

Jump to IBS2009              Jump to NMRS2009             Jump to NSC-11
Jump to NSC-12             Jump to IBS-2010             Jump to NMRS2010

Images copied from the WebSite for NMRS2009

CLICK on this picture to display biodata of Dr.Aravamudhan          CLICK here to display the webpage for NMRS2008 participation
Dr.S.Aravamudhan          Logo "NMRS2009"           


Link:-  The First Bruker Pre-NMRS Symposium in INDIA
Place the cursor on the images and wait for "mouse-over messages" to appear

CLICK HERE for the organizational Website for NMRS2009

CLICK HERE   and find updated [as received from organizers on 6th Jan.2009] list of participants, titles of abstracts, accommodation request and details of their travel.The same information will be posted on webpage (www.nmrs2009.org/linked to image above)


Entry Number(S.No) 158 in the list is as below;
158    M    DR.    ARAVAMUDHAN    SANKARAMPADI    GUEST PROF.    NEH UNIV.,SHILLONG
    2    5    Y    N      inboxnehu_sa@yahoo.com     THE NECESSITY FOR A PROTOCOL FOR PROCESSING AFTER EXPERIMENTAL MEASUREMENT OF PROTON SHIELDING TENSOR IN SINGLE-CRYSTAL SPECIMEN

posted at Kolkata Airport on 7th Jan.2009 at 3:47 PM


Abstract for NMRS2009      Jump to IBS2009

CLICK HERE  to download the MSWORD document of the Abstract_nmrs2009

Scientific Program           List of people presententing abstracts

CLICK HERE for a page of Symposium on

THE NECESSITY FOR A PROTOCOL FOR PROCESSING AFTER EXPERIMENTAL MEASUREMENT OF PROTON SHIELDING TENSOR IN SINGLE-CRYSTAL SPECIMEN

S.ARAVAMUDHAN
Department of Chemistry
NORTH EASTERN HILL UNIVERSITY
SHILLONG 793022 Meghalaya

The context here is the measurements of Shielding Tensor of protons in solid-state single-crystal specimen. The experiments yield the values of the components and the direction cosines of the principal directions of the Tensor. Further after, In order to obtain the information on the molecular electronic properties (in the case of single crystals of organic molecules) it becomes necessary to properly account for the near neighbor inter molecular contribution to the shielding at a given site; and the bulk susceptibility contribution to the induced fields at this site. Thus, the subsequent processing, required after obtaining the experimentally measured values, has been a discouraging factor in the HR PMR studies using the multiple pulse line narrowing techniques. This has relegated such HR PMR studies even more because of the current day advances in the multi nuclear multi dimensional techniques and the corresponding improvements in the spectrometer features. However, in spite of all such trends and improvements there has been no unequivocal evidence(1) that there would not be situations arising when a structural characteristic can be established only with the HR PMR measurements also made for conclusive evidences. Such situations may not be a routine these days, but still there is a necessity to provide a protocol for the processing after the experimental measurement (2).

An enumeration of the results till now is intended in this contribution envisaging a protocol for measurements by HR PMR using multiple pulse line narrowing technique. The various steps taken till now to obtain clarifications(3) on the accounting of bulk susceptibility contributions(4) are enumerated systematically realizing a protocol which would be valid for any shape of the specimen of all molecular systems for which a single crystal can be obtained(5).


             1. http://www.geocities.com/saravamudhan1944/eenc_ampere_lille.html#Section_4
             2. http://nehuacin.tripod.com/id4.html )  (EUROMAR2007)
             3. http://nehuacin.tripod.com/id6.html   (FD NMR; Sheet-10 of display sheets)
             4. http://nehuacin.tripod.com/id3.html   (4th Alpine SSNMR Conference)
             5. http://www.geocities.com/inboxnehu_sa/nmrs2009.html


inboxnehu_sa@yahoo.com



Materials for A POSTER PRESENTATION:   Download Postersite Layout
Acceptance of Abstract received on January 15, 2009 while at Chennai  


Sheet_01
Sheet_02
Sheet_03
Sheet_04
Sheet_05
Sheet_06
Sheet_07
Sheet_08
Sheet_09
Sheet_10_11_12           Sheet_13

THE OVERALL PROCEDURE

DOWN LOAD "OVERALL PROCEDURE"

1. The sample is of arbitrary Shape.
2. Obtain a set of x, y, z coordinate values, which when tabulated can
    conveniently provide the reconstruction of the shape of the specimen. This
    could be a laboratory experiment (as described in Sheets #11 and #12 in this
   poster display) which has to be standardized by considering the specimen of
    typical shapes and the requirements for the Calculation of bulk susceptibility
   effects as described in Sheets #7 and #8 of this display.
3. Orient the specimens and make the HR PMR measurement to obtain the
    rotation pattern. Compute for the Principal Directions and Component values
    of the measured Shielding Tensor.
4. Calculate the inter-molecular contribution to shielding tensor by discretely
    summing within a semi micro volume element as described in Sheets #2, #3,
    #5
. Subtract this inter-molecular contribution from the measured
   experimental Tensor values
.
5. Calculate the shape-dependent values due to the bulk susceptibility effects as
   described in Sheets #7 and #8. Subtract this calculated tensor for shape
   dependent contributions from the result of step 4 above
.
6. The value of the tensor obtained as a result at stage 5
   should be the required INTERMOLECULAR
   SHIELDING TENSOR
.


CLICK here on the image for the full size view


NMRS 2010
update on 25 Feb 2010 at Delhi
http://www.nmrs2010.org    Feb. 21-24, 2010 at CBMR, SGPGIMS, Lucknow     http://cbmr.res.in/

The Contents of the NMRS2010 is also based on the contents of:
http://www.angelfire.com/art3/saravamudhan/iitm_crsi_ismar_ca98.html
http://aravamudhan-s.ucoz.com/amudhan20012000/ismar_ca98.html


ABSTRACT for NMRS2010

VARIATION OF CHEMICAL SHIFTS WITH MOLECULAR GEOMETRY
THROUGH THE EQUILIBRIUM CORRESPONDING TO A
GEOMETRY OPTIMIZATION


S.ARAVAMUDHAN
Department of Chemistry
NORTH EASTERN HILL UNIVERSITY
SHILLONG 793022 Meghalaya

When the Geometry Optimization for equilibrium (stable) geometry procedure is explained on the basis of the applicability of variation principle, then the molecule passes through a minimum of potential energy to recognize the most stable structure as corresponding to the minimum. For such a passage through a series of structures on both sides of the minimum energy, if the chemical shifts of the nuclei in the molecule are also calculated for the series of structures, would there be a possibility to recognize the characteristics of the stable structures? This is a pertinent question and since the Computational methods result in the Full Tensor element values (not merely the isotropic, trace value), it is probably worth the while looking into the above question, with the variation of the chemical shift tensor properties tracked through the series of structures encountered during the geometry optimization procedure.

For this perspective a beginning can be made with what ever effort is known in the literature to document the chemical shift dependence on the geometry parameters. Since the Solid State High Resolution NMR is gaining in importance in structure determination (small molecules, and polymeric macro molecules also of biologically relevant) a question of the variation of chemical shift with geometry, and explaining the trends on the basis of the electron population analysis would lead to a situation of using full tensor information similar to the way chemists these days interpret the isotropic liquid HR NMR spectra. In this context the consideration in the cited reference (1) for the trends of methyl group proton (isotropic and anisotropic part of the) chemical shift tensor can be viewed from the point of view of the available electronic structure information by the quantum chemical computation for the electron distribution within the molecule. The relevance of such considerations would be highlighted with regard to the HR Single Crystal PMR results as in cited reference (2).


REFERENCES:
1. Die magnetische Abschirmung von Protonen in Methylgruppen und aromatischen Ringen: Multipuls-NMR-Experimente an Molekulkristallen : Inaugural-Dissertation zur Erlangung der Doctorw?e der Naturwissenschftlich-Mathematichen Gesamtfakult䀴 der Ruprecht-Karls-Universit䀴, Heidelberg. Vorgelect von Dipl.-Phys. Bernd Tesche aus L?nscheid, Tag der m?liche Prufung 19-07-1995

2. The proton nuclear magnetic shielding tensors in biphenyl: Experiment and Theory ,  Frank Schonborn, Heike Schmitt, Herbert Zimmermann, Ulrich Haeberlen, Clemence Corminboeuf, Gilbert Grossmann, Thomas Heine, J.Mag.Res. 175, (2005), 52-64.

Also note the contents at: http://www.geocities.com/saravamudhan1944/eenc_ampere_lille.html#Section_4 
and  http://geocities.com/inboxnehu_sa/Poster_Sheets_Ampere.html

Email:-   inboxnehu_sa@yahoo.com


A computation of the Absoulute Chemical shifts after the NMRS2010:
On METHANE for bond distance of only one bond varied

                                                                                                                                                                        Upoaded on May 10, 2010, at NEHU Campus Shillong

Click on image for the display in full size
Click on image for the display in full size

DOWNLOAD the 12 Poster sheets from the Link:
POSTER SHEETS of NMRS2010
http://www.angelfire.com/art3/saravamudhan/iitm_crsi_ismar_ca98.html
http://aravamudhan-s.ucoz.com/amudhan20012000/ismar_ca98.html


Following images of NMRS2010 uploaded on 27th Feb. 2010 at Guwahati

Cover page of NMRS2010 Abstract book: Click on image for enlarged view
Programs page of NMRS2010 with PP97 enlisted: Click on image for enlarged view
Page of NMRS2010 Abstract book containing Aravamudhan's Abstract: Click on image for enlarged view
A view from the CBMR auditorium

A view during the Technical Sessions NMRS2010 at "Shruti" Auditorium: SGPGIMS, Lucknow
Click HERE for another picture: View at the inaugural session NMRS2010
Click on image for enlarged view: April 07, 2010

CLICK HERE  for a set of introductory Video lectures on NMR: A webpage link at http://www.nmrwiki.org

Jump to Top of Page

Jump to IBS2009              Jump to NMRS2009             Jump to NSC-11
Jump to NSC-12             Jump to IBS-2010             Jump to NMRS2010

IBS 2009
During 27-31 Jan. 2009 Dr. Aravamudhan was at the IGNOU, New Delhi for consultations with the Pro-Vice-Chancellor Prof. K.R. Srivathsan in connection with a "WORKSHOP ON E-LEARNING WITH FOCUS TO EDUCATIONAL INTERNET DOMAINS" to be held at the Computer Centre, N.E.H.U. Some of the considerations on the theme for the workshop are included in the Downloadable link :  E-Learning Workshop  This document essentially describes the needs as does arise for students with educational backgrounds from the North Eastern Region
CLICK on image to display the website of CCMB, Hyderabad

Jump to IBS2009              Jump to NMRS2009            Jump to NSC-11

CLICK on image to display the website of IBS2009 at CCMB, Hyderabad
The materials for presentation in  IBS2009  are based essentially on the materials of the IBS2007.

This author could not attend the IBS2007 due to turn of events beyond control hence the materials remained unpresented.
The Poster materials of IBS2007 can be viwed from  HERE,..Click!

POSTER SITE of IBS2009 created on Wednesday, January 21, 2009 at IICT Guest House, Hyderabad--S.Aravamudhan
POSTER SITE IBS2009:NCMB2009
Poster #P94   CLICK HERE   to display the list of Abstracts as extracted from the URL: http://ccmb.res.in/ibs_2009/abstract.pdf and added to this page on 21 Jan. 2009 at 11:50 AM


ABSTRACT: IBS2009
Find on page 92 of the NCMB-2009 Symposium ABSTRACTA BOOK

FULL TENSOR FORM FOR CALCULATING RING CURRENT SHIFTS
GENERATING WEIGHT FACTORS OF THE INSTANTANEOUS CHEMICAL SHIFT VALUES
FOR AN EFFECTIVE MOTIONAL AVERAGING IN BIOLOGICAL MOLECULES


S. ARAVAMUDHAN
Department of Chemistry
North Eastern Hill University
SHILLONG 793022 Meghalaya

inboxnehu_sa@yahoo.com

By using the Full Tensor Form of the equation for the aromatic ring current shifts in the , it has been possible to show (1) that there are definite advantages of calculating the full shielding tensor for such cases of molecules in motion, rather than merely using the equations for the isotropic shift values. However, in the model calculation presented (2) equal weights were given for the shift values sampled at the several instantaneous dispositions during the motion while arriving at a average value. Conventionally, an oscillatory motion (torsion) is satisfactorily taken into account on the basis of the characteristics of Simple Harmonic Motion. In such a case the characteristic resident time for the molecule at a point during the oscillation can determine the weight factor. Such criteria if it gets built in to the averaging procedure, then the results could have better confidence indices. An approach of this type would be illustrated and to whatever extent possible a comparison with the approaches as in Reference (3&4) would be presented. Indications to the observable trends in the chemical shifts become evident in the results obtainable in tabular form and or graphical plots.

Refrerences:-
(1). http://www.geocities.com/sankrampadi/ForIbs2006.html Poster Sheet_11:
(2). http://www.geocities.com/sankrampadi/ForIbs2006.html Poster Sheets_10 & 11:
(3). ?uctuations and Averaging of Proton Chemical Shifts in the Bovine Pancreatic Trypsin Inhibitor?t;/I> Jeffrey C. Hoch, Christopher M. Dobson, and Martin Karplus, Biochemistry 21, 1118-1125 (1982)
(4). http://in.geocities.com/saravamudhan2002/events_2007.html


CLICK on image to display the home page of IBS2009

SHEETS-01 to 03 consist of excerpts from an early application of isotropic ring current shift values to the context of macromolecular fluctuations. SHEET-04 describes the efforts initiated for the calculation of FULL TENSOR instead of only the trace.

Display SHEETS 05 to 09 contain the results of a calculation as per the considerations of SHM weight factors discussed in the Previous SHEET-03.

SHEET-09 consist the essential results as can be summarised till the present.

SHEETS 10 to 12 contain the results displayed in the previous years?BS events on the necessity for the calculation of ring current shits in Full Tensor FORM. The illustrations in this presentation of the considerations on the trends in weight factors while averaging are once again mainly with isotropic calculation trends. But the results as presented indicate well how the differences can improve significantly the conclusions with appropriate option on the specific tensor component should be relevant and for such a specified component how the criteria for relative weight factors can be adapted

Sheet-01
Sheet-02
Sheet-03
Sheet-04
Sheet-05
Sheet-06
Sheet-07
Sheet-08
Sheet-09
Sheet-10
Sheet-11
Sheet-12


Click on the image for the fullsize display
This certificate uploaded on 28 Jan. 2009 at IGNOU, New Delhi

IBS-2010
The following images of IBS2010 uploaded on 27th Feb. 2010 at Guwahati
Invitation to Chair session at IBS2010: Click on image for enlarged view
Invitation to Prof. S. Aravamudhan from the Convener IBS2010 Prof.P.C.Mishra to Chair a session at IBS2010
Cover page of IBS2010 Abstract book: Click on image for enlarged view
A Sheet from Programs in IBS2010 Abstract book: Click on image for enlarged view
Dr. Aravamudhan receiving Momento from the Convener Prof. Mishra, after Chairing the Session: Click on image for enlarged view

Dr. Aravamudhan receiving aMomento from the Convener IBS2010, Prof. Mishra:- after Chairing the session.
Jump to Top of Page

Jump to IBS2009              Jump to NMRS2009             Jump to NSC-11
Jump to NSC-12             Jump to IBS-2010             Jump to NMRS2010


NSC-11          11th National Symposium on Chemistry (of the CRSI):
National Chemical Laboratory, PUNE
February 5-8, 2009



Click HERE to display the website for nsc11 http://www.ncl-india.org/nsc-11
ABSTRACT NSC-11

AN APPROACH TOWARDS A DESCRIPTION FOR NQR PHENOMENON
IN TERMS OF CLASSICAL VECTOR PRECESSION:

An effort for the appreciation of Chemists, highlighting similarities and differences in
the NMR and NQR Phenomena

S.ARAVAMUDHAN
Department of Chemistry
North Eastern Hill University
SHILLONG 793022 Meghalaya


inboxnehu_sa@yahoo.com

The induced transitions, in presence of the electromagnetic radiations in the Radio Frequency region responsible for Nuclear Quadrupole Resonance (referring explicitly to NQR at zero external magnetic field) are magnetic dipole transitions in nature as much as the NMR transitions are. But, the energy of interactions which cause the energy level splitting in the two cases are different. In the case of NMR it is the magnetic dipole vector interacting with the External Magnetic fields (external to the sample containing the ensemble of spins) which causes energy level splitting. On the other hand the basic interaction for the NQR is the Nuclear Quadrupole Moment Tensor with the Electric Field Gradient Tensor within the specimen, but external to the particular nucleus.

The classical vector precession picture can be conveniently used to convince in the Chemistry class rooms to get convinced about the parameters which are relevant to chemists. But a similar visualization is not possible for NQR as can be found from several sources. Efforts were made to use the classical vector description for the Bulk Magnetization in the context of NQR, but the classical vector description of the type of nuclear spin precession to describe NQR phenomenon is totally absent. It is because the nuclear quadrupole moment is described and discussed under nuclear physics and the Tensor interactions are describable conveniently by mathematical expressions but visualization of ?nsors?s not as easy as the visualization of ?ctor?uantities.

In this paper the tensor interactions and the differences between Magnetic Field Vectors, and the Electric Field Gradient Tensors are being discussed by schematically representing the fields and field gradients in terms of the trends of the ?nes of forces?epresenting the fields. Then the association of the magnetic moment with the spin angular momentum is compared with the difficult task of associating the spin angular momentum vector with the Nuclear Quadrupole Moment Tensor. After arriving at a ?uivalent?escription of an association of an effective line to represent quadrupole property (even though in reality such a line may not exist) that line is ?pposed?o hold a fixed orientation with respect to the Spin angular momentum, by virtue of which a classical vector precession picture becomes tangible. And, this would really enable the necessary basics about the interactions in NQR to be grasped with an awareness as to why the descriptions cannot be as simple. Even though, even without such a study, pulsed NQR experiments are being performed and described in terms of density matrices and the utility of the phenomenon has been so well established. But the appreciation of the pulsed NQR experiments by the Chemists who use this technique remains only vague and elusive for the grasp. Hence descriptions as basic as that of dipole moments1 would be presented for the quadrupole moment to bring the phenomenon under better grasp. An indications to what this approach would be has been made available2 for viewing.

Reference:-
      1.  http://www.geocities.com/saravamudhan1944/crsi_6nsc_iitk.html
      2.  
2. http://in.geocities.com/saravamudhan2002/NMRS2008.html


CLICK HERE   to Download COPY of   NSC-11 ABSTRACTS BOOK   as ".pdf " file of 7MB Size
This Abstract book was in the CD Form as part of the Registration Material

POSTER SITE NSC-11
NOTE:-The order in which these Poster sheets are arranged in the table below and the contents might be
slightly different from the way the presentation was made on 7th Feb. 2009
  
INDEX to the Contents of Display Sheets


        SHEET-01  CONTENTS INDEX

      SHEET-02 & SHEET-03  INTRODUCTORY NQR

      SHEET-04  DESCRIBING FIELD GRADIENTS

       SHEET-05    Nuclear Charge Distribution: Spherical versus Non Spherical Non Spherical distribution of
                                   charge and the Quadrupole moment; The possibility of a
                                   linear arrangement for the Quadrupole

      SHEET-06  Nucleus; Nuclear Quadrupole moment; and the Nuclear Spin Angular Momentum

       SHEET-07   Interaction of the Dipole with Uniform Field and the Quadrupole with Uniform (linear)
                                   Field Gradient

       SHEET-08   Disposition of the various vector quantities and the linear quadrupole moment of nucleus

       SHEET-09   Quantization of Angular momentum while Quadrupole moment Interacts with Field Gradient

       SHEET-10   A Energy Level Diagram for Comparing NMR and NQR interactions

       SHEET-11   Envisaging a Precession Picture for NMR and NQR

       SHEET-12   What is right and What is wrong with the Question in this Sheet ?

SHEET-01
SHEET-02
SHEET-03
SHEET-04
SHEET-05
SHEET-06
SHEET-07
SHEET-08
SHEET-09
SHEET-10
SHEET-11
SHEET-12

CLICK here on the image for the full size view


NSC12
POSTER SITE NSC12
Sheets uploaded on Jan. 27, 2010 at NEHU, Shillong


http://www.iictindia.org/nsc12
List of Accepted Abstracts   Find Aravamudhan's Abstract as the first Abstract on Page 18 [of 22pages]


Click on image for enlarged view
Click on image for enlarged view
ABSTRACT NSC-12

SINGLE SPIN VECTOR PRECESSION DESCRIPTION FOR NQR:
AND POPULATIONS, MAGNETIZATION AND COHERENCES


S. ARAVAMUDHAN
Department of Chemistry
NORTH EASTERN HILL UNIVERTSITY
PO NEHU Campus SHILLONG 793022
Meghalaya INDIA

In the previous presentation (1, 2) the feasibility of a classical vector precession description was considered for NQR and a provisional illustration could be worked out for such a single spin description for the case of the basic NQR interaction of Electric Field Gradients interacting with Nuclear Quadrupole Moment. The further consequence which can be looked for is the possibility of describing the Resonance Phenomenon using the single spin description and envisage a coverage of the description of terms like Population, Magnetization and Coherences and the description of evolution of the spin system in accordance with the classical vector single spin precession under nuclear quadrupole interactions.

These terms have a well formulated description for the case of NMR of spin ? nuclei like protons. A description for the NMR of Spin >1 nuclei (with three equidistant energy levels for Spin=1 unlike the two level system for spin ?) and the corresponding NQR level descriptions have to be considered for a convincing development of the meaning of the terms like populations, magnetization, and the coherences arising out of superposition of levels under short intense pulses applied to the spin system.

This aspect would be considered and the credible alternatives for NMR and NQR would be attempted when the nuclear spin is >1

Reference:
1. http://aravamudhan-s.ucoz.com/nmrs2009_ibs2009_nsc11.html#NSC-11
2. http://ugc-inno-nehu.com/

Soon after the Poster presentation of the NSC12 Abstract, this author found somewhat a similar effort to describe  the two-spin Coherently-superposed NMR states  by nonclassical vector diagrams.However the effort in above abstract is for an evolution to reach out for the description of NQR phenomenon.----        inserted on 19th March 2010 at Shillong
SPIN-1/2 AND BEYOND: A Perspective in Solid State NMR Spectroscopy; --an article by Lucio Frydman, Annu. Rev. Phys. Chem. 2001. 52:463–98.----   Link provided on 22nd July, 2011 at BIC,NEHU, Shillong

The Photographs at the venue were uploaded in Chennai on 8th Feb 2010 soon after return from the vanue after the participation in NSC12 in Hyderabad
Click on image to display Certificate
Click on image for enlarged view

DOWNLOAD the 12 Poster sheets from the Link:
POSTER SHEETS of NSC12
Click on image for enlarged view

Jump to Top of Page