An International Peer Reviewed Research Journal

AJP Vol 5 No 3, 1996

AJP

SSN : 0971 - 3093

Vol  5, No. 3, July-September, 1996

Vol 5, No 3, 1996


Asian Journal of Physics                                                                                                                     Vol 5, No 3(1996) 225-229


Direction-cosines for barrier height determination:A general formalism


R Shanker and  R A Yadav

Department of Physics

Banaras Hindu University, Varanasi-221 005, India

__________________________________________________________________________________________________________________________________________

In determining barrier height of a top against free rotation, one requires the direction cosines of the top- axis relative to the principal axes. Determination of direction- cosines  for a top-axis in a non-planar molecule is not straight-forward. Therefore, a general formalism to determine direction- cosines of a top -axis has been presented for the first time.

References

1. Durig J R, Craven S M & Harris W C, Vibrational Spectra and Structure, Vol 1, Edited by J R Durig,(Marcel Dekker Inc,N Y),1972, p 73

2. Hirschfelder J O. J Chem Phys, 8(1940)431.

3. Colthap N B, Daly L H & Wiberley S E, Introduction to Infrared and Raman Spectroscopy,(Academic Press, N Y and London),1964.

4.Gerald C F, Applied Numerical Analysis, 2nd Edn, (Addison-Wesley Publishing Co, Inc Cambridge, Mass (USA), page 50, (1978)

5.Shanker R , Ph D thesis, Banaras Hindu University, India, 1994.

Direction-cosines for barrier height determination:A general formalism.pdf
R Shanker and R A Yadav

___________________________________________________________________________________________________________________________________


Asian Journal of Physics                                                                                                                       Vol 5, No 3(1996) 231-233


Laser Raman and IR spectra of complex of Co(II) with 2-thiouracil


Chander Bala Arora, Rachna Rastogi, Usha Awasthi* and Krishna

Department of Physics

Lajpat Rai College, Sahibabad-201 005, India

*Department of Zoology, Govt Girls College, Rewa, India

___________________________________________________________________________________________________________________________________

Stable complex of Co(II) with 2-thiouracil of the composition [Co(C4H4N2OS)3H2O] has been isolated in the solid state, and characterized on the basis of chemical analysis, magnetic measurement, IR and Raman spectral studies. The spectral studies indicate that the ligand 2-thiouracil acts as monodentate and coordination takes place through sulphur of (C2=S) group.

The ligand and its Co-complex were tested for their activity against Dalton’s lymphoma and it was found that they are effective antitumor agents.

References

1. Rastogi V K, Lal B, Sharma Y C & Jain C L, Metal ions in biology and medicine, (John Libbey, Eurotext, France), 1992, p 184

2. Rastogi V K, Singh Ajay, Chawla S C & Gupta S L, Procd 5th European Conf on the Spectroscopy of Biomolecules, (Kluwer Academic Publications, The

    Netherlands),1993,p 203.

3. Rastogi V K, Mital H P & Sharma S N, Indian J Phys B, 64 (1990) 312.

4. Rastogi V K, Lal B, Arora C B & Gupta S L, Procd. IXV International Conf on Raman Spectroscopy, (John Wiley & Sons, N Y)), 1994,p 952.

5. Sathyanarayana D N &  Kashmir Raja S V, Spectrochim Acta, A41(1985)809

6. Rastogi V K,  Singhal S K, Upadhyay M & Dublish A K, Procd.XV International Conf on Raman Spectroscopy, (John Wiley & Sons), 1996.

___________________________________________________________________________________________________________________________________



Asian Journal of Physics                                                                                                                         Vol 5, No 3(1996) 235


Thermodynamics of 4-amino-2-chlorobenzonitrile molecule


Sudhir Kumar1 D K Jain2, Sushma Arora1 and Y C Sharma3

1Department of Physics, Lajpat Rai College, Sahibabad-201 005, India

2Department of Physics, Meerut College, Meerut-250 001, Meerut

3Department of Physics, NAS College, Meerut, India

 ___________________________________________________________________________________________________________________________________

The present note reports the thermodynamical functions viz enthalpy, heat capacity, free energy and entropy of 4-amino-2-chlorobenzonitrile molecule, calculated using vibrational frequencies obtained from IR and Raman spectra of the molecule.

References

1. Sharma Y C, Yadav B S & Pandey A N, Asian J Phys, 3(1993)175.

2. Rastogi V K, Jain D K & Sharma Y C, Asian J Chem, 3(1991)113

3.Hellwege K H & Hellwege A M (Eds), Landolt Barnstein Numerical Data and Fundamental Relationships in Science and Technology New Series: Structural Data for Free Molecules, (Atomic and Molecular Physics), Vol 7, 1976 and Supplement to volume II/7, Vol 15, 1987. Springer Verlag, Berlin, 1976,1987.

___________________________________________________________________________________________________________________________________


Asian Journal of Physics                                                                                                                  Vol 5, No 3,(1996) 245-246


FTIR and laser Raman spectra of complex of Mn(II) with 2-thiouracil


J K Gupta, Sudhir Kumar, Satyendra Kumar and S D Kaushik*

Department of Physics

L R College (CCS University, Meerut),Sahibabad-201 005, India

Department of Chemistry, L R College, Sahibabad-201 005, India

___________________________________________________________________________________________________________________________________

Metal complexes of Mn(II) with 2-thiouracil of the composition [Mn(C4H4N2OS)3H2O] has been synthesized and characterized on the basis of chemical analysis, magnetic measurement, IR and Raman spectral studies. The spectral studies indicate that the ligand 2-thiouracil acts as monodentate and coordination takes place through sulphur of (C2=S) group. © Anita Publications. All rights reserved.

___________________________________________________________________________________________________________________________________


Asian Journal of Physics                                                                                                                    Vol 5, No 3(1996) 247-248


FTIR and laser Raman spectra of 5-iodourail


Sudhir Kumar, S K Singhal1, J P Goel2 and M Srivastava3

Physics Department, L R College, Sahibabad-201 005, India

1 Department of Physics,Agrasain Degree College, Sikandarabad-203 205,India

2 Department of Physics, Meerut College, Meerut-250 001, India

3 Department of Chemistry, L R College, Sahibabad-201 005, India

___________________________________________________________________________________________________________________________________

FTIR (200-4600 cm-1) and laser Raman(10-2000 cm-1) spectra of 5-iodouracil have been recorded. The spectra have been analysed assuming Cs point group symmetry and the observed fundamentals have been assigned to different normal modes of vibration. ©Anita Publications All rights reserved.

References

1. Sharma V, Sharma S D, Seema,Yada B S, Asian J Phys, 3(194)229.

2. Bandekaar J, Zundel G, Spectrochim Acta, 39A(1983)343.

3. Szezesniak M, Nowak M J, Rostkowska H, Szezesniak K, Person W B, Shugar D, J Am Chem Soc,105(1983)5969.

4. Rastogi V K,Mital H P, Sharma S N, Indian J Phys, 64B(1990)312.

5. Rastogi V K, Mital H P, Sharma Y C, Sharma S N, Spectroscopy of Biological Molecules, Eds R E Hester, R B Girling, (Royal Society of Chemistry),1991, p

    403.

6. Rastogi V K, Lal B, Sharma Y C, Jain C L, Metal ions in Biology and Medicine, Vol 3, Eds J Anastassopoulou, P Collery, J-C Etienne, Th Theophanides, (John

    Libbey Eurotext, France), 1990, p 184.

___________________________________________________________________________________________________________________________________


Asian Journal of Physics                                                                                                                  Vol. 5, No 3 (1996) 283 -289


Emission and Excitation Studies in Eu2+ and Mn2+ Doped KBr


A K Mishra

Physics Department, NAS College, Meerut- 250 004 , India

and

S D Pandey  

cPhysics Department, PPN College, Kanpur- 2008 001,  India

___________________________________________________________________________________________________________________________________

The optical emission and excitation spectral studies in KBr: Eu2+ and Mn2+ single crystals  at, different sample conditions have been analysed to identify the various aggregates and precipitates of both impurities and possible energy transfer from one impurity to another. The emission  obtained at 525 nm in the  both grown samples at  RT and LNT is proposed to be due to radiative energy transfer from Eu2+  to  Mn2+ ions, the latter being in Suzuki phase. The RT emission spectra of the samples annealed  for long time at 220 °C and LNT emission spectra of as grown samples identify the growth of different aggregates of Eu2+  and Mn2+ ions at the expense of (I-V) dipoles of the two impurities. © Anita Publications. All rights reserved.

Keywords: KBr, Suzuki phase, Eu2+ and Mn2+ single crystals

Total Refs: 31

___________________________________________________________________________________________________________________________________

1 Introduction

         Many investigations have been devoted to divalent impurity doped  alkali halide crystals which exhibt intetresting peculiarities due to the presence of a cation vacancy compensating the electrical extra charge of the divalent ion. The resulting (I-V) pairs have been studied by different techniques as optical [1-5], EPR [6], ITC and ionic conductivity studies [8].

            Particularly, the optical properties of Eu2+ ions in alkali halides are fairly well understood. The Eu2+ -ions doped in KBr host have two absorption bands [3] in the UV region of the spectrum, with peak positions at 250 nm and 344 nm. These bands are due to dipole allowed transitions from the ground state 8S7/2 of Eu2+ ions to the splitted crystal field 5d orbitals. The high-energy band is due to transitions  from the ground statet of  the Eg component of the 4 f 6(5d) configuration, while the low energy band is attributed to the T2g component of this configuration. As these transitions are dipole allowed, their oscillator strengths are high making the Eu2+ -doped KBr system an efficient absorber of UV light.

            The optical properties [9,10] of Mn2+ ions in alkali halides are also fairly well understood. The absorption bands of Mn2+ ions in alkali halides  are relatively weak because these arises from spin and parity forbidden transitions. The oscillator strength of these transitions is around 10–7, which  makes Mn2+  doped systems weak absorbers of UV light. 

© ANITA PUBLICATIONS

All rights reserved

Designed & Maintained by

Manoj Kumar