DOCTOR OF PHILOSOPHY IN PHYSICS

Thesis submitted to the Bharathidasan University, Tiruchirappalli

in partial fulfilment of the requirements for the award of the degree of

INVESTIGATION ON THE GROWTH AND

PROPERTIES OF SOME ORGANIC AND

SEMI ORGANIC NONLINEAR OPTICAL

SINGLE CRYSTALS

Dr. S. ALFRED CECIL RAJ, M.Sc., M.Phil., Ph.D.,

ByMrs. A. RUBY, M.Sc., M.Phil., B.Ed.,

(Ref. No:10464/PhD1/Physics/PT/ Re-regn./Oct. 2011)

Under the Guidance of

DEPARTMENT OF PHYSICS

St. JOSEPH’S COLLEGE (Autonomous)

TIRUCHIRAPPALLI - 620 002, INDIA

Accredited at ‘A’ Grade (3 Cycle) by NAAC & College with Poten tial for Excellence by UGCrd

MARCH 2013

i

Dr. S. ALFRED CECIL RAJ, M.Sc., M.Phil., Ph.D., Associate Professor Department of Physics St. Joseph’s College (Autonomous) Tiruchirappalli - 620 002 Tamil Nadu, India.

CERTIFICATE

This is to certify that the thesis entitled “INVESTIGATION ON

THE GROWTH AND PROPERTIES OF SOME ORGANIC AND

SEMI ORGANIC NONLINEAR OPTICAL SINGLE CRYSTALS”

submitted by Mrs. A. RUBY is a bonofide record of research work done by her

during the period of study 2009-2013 under my supervision in the Department

of Physics, St. Joseph’s College (Autonomous), Tiruchirappalli - 620 002,

Tamil Nadu, India and that the thesis has not previously formed the basis for

the award of any Degree, Diploma, Associateship, Fellowship or any other

similar title. The thesis represents an independent work on the part of the

candidate.

Tiruchirappalli - 620 002 Dr. S. ALFRED CECIL RAJ Research Supervisor

ii

A. RUBY Research Scholar Department of Physics St. Joseph’s College (Autonomous) Tiruchirappalli - 620 002.

DECLARATION

I hereby declare that the work presented in the thesis entitled

“INVESTIGATION ON THE GROWTH AND PROPERTIES OF

SOME ORGANIC AND SEMI ORGANIC NONLINEAR OPTICAL

SINGLE CRYSTALS” has been originally carried out by me independently

as a part time research scholar during 2009-2013 under the guidance of

Dr. S. ALFRED CECIL RAJ, Associate Professor, Department of Physics,

St. Joseph’s College (Autonomous), Tiruchirappalli - 620 002, Tamil nadu, India.

This work has not been submitted either in whole or in part for any other

Degree or Diploma at any University or Research Institute.

Tiruchirappalli - 620 002 A. RUBY

iii

ACKNOWLEDGEMENT

First I bow my head before God Almighty for His unending grace and

I thank the Lord for giving me good health and spirit to complete the research

work successfully.

I take immense pleasure to thank, admire and appreciate the person

behind this thesis Dr. S. Alfred Cecil Raj, Associate professor, Department

of Physics, St. Joseph’s College (Autonomous), Tiruchirappalli, my Research

supervisor, whose invaluable suggestions, insipiration and incessant encouragement

helped me to complete this task efficiently. I am deeply indebted to him for his

valuable advice, patience and guidance.

I thank Prof. Dr. K. Ramamurthi, Professor and Prof. Dr. R. Ramesh

Babu, Assistant Professor, School of Physics, Bharathidasan University,

Tiruchirappalli, for their kind encouragement towards research.

I wish to thank the former principal Rev. Dr. Sebastian Anand SJ

and the present principal Rev. Dr. A. Albert Muthumalai SJ, St. Joseph’s

College (Autonomous), Tiruchirappalli, for allowing me to persue research in

the institution.

Immense thanks are due to Prof. K. Sundar Sekar, Associate professor

and former Head and Prof. Dr. Victor Williams, Associate professor and

Head, Department of Physics, St. Joseph’s College (Autonomous), Tiruchirappalli.

I express my gratitude to Dr. K. Maria Eugine Pia, Associate Professor,

Department of Physics, Holy Cross College (Autonomous), Tiruchirappalli, the

doctoral committee member for her valuable suggestions throughout the course

of my research work.

iv

I express my profound thanks to Prof. V. Gokula Krishnan, Assistant

Professor, Science and Humanities, Balaji institute of Engineering and

Technology, Chennai, Prof. Dr. G. Pasupathi, Assistant Professor,

Department of Physics, AVVM Sri Pushpam College (Autonomous), Poondi,

Thanjavur and Mrs. P. Kalai Selvi, Research Scholar, Department of Physics,

St. Joseph’s College (Autonomous), Tiruchirappalli, for their help and encouragement

in all possible ways.

I thank the Head, SAIF, IIT-M, Chennai for single crystal X-ray

diffraction (XRD) analysis and the Nuclear Physics department, University of

Madras for powder XRD studies. I am thankful to Prof. Dr. P.K. Das,

Department of Inorganic and Physical chemistry, IISc, Bangalore for extending

the facility for SHG studies. I am grateful to the Head, CECRI, Karaikudi, for

extending the experiment of thermal and elemental analysis. My sincere thanks

to Dr. D. Sastikumar, Department of Physics, NIT, Tiruchirappalli, for

providing Z-scan experimental facilities. My heartfelt thanks to Mr. Y. Vincent

Sagayaraj, Archbishop Casmir Instrumentation Centre, St. Joseph’s College

(Autonomous), Tiruchirappalli, for his sincere help in characterization studies.

It is my pleasant duty to express my thanks to all those who gave kind

support and encouragement for my research work. Last, but not the least,

I express my sincere gratitude to my mother Mrs. A. Periyanayagam, Rtd.

Teacher, for her love and sacrifice which made me sustain all through and

I dedicate this work to her.

A.A.A.A. RubyRubyRubyRuby

v

CONTENTS

Chapter No.

Title Page No.

List of Tables vi

List of Figures vii

List of Publications x

Abbreviations xii

Symbols xiii

Preface xv

I. Introduction to nonlinear optics and nonlinear optical single crystals

1

II. Synthesis, crystal growth and X-ray diffraction analysis 47

III. Vibrational and Elemental Studies 76

IV. Thermal and Mechanical Properties 96

V. Dielectric Properties 122

VI. Linear and nonlinear optical properties 143

VII. Summary and Scope for Future Work 166

References R 1

Papers Published

vi

LIST OF TABLES

Table No.

Title Page No.

1.1 Some of the NLO materials of Valine, glycine and Thiourea 38

2.1 Lattice parameters of LVZA and L-Valine 68

2.2 Lattice parameters of GM 69

2.3 Comparison of lattice parameters Glycine, TU and GT 70

2.4 Lattice parameters of TCZC and TuTGZC crystals 70

2.5 Comparison of lattice parameters of Tu, BTCC, BTZC, ZTS, BTSF and BTSN

71

2.6 Comparison of lattice parameters of TPMS with MTS 72

3.1 Assignment of FTIR wavenumbers (cm-1) for LVZA, and L-Valine

80

3.2 Assignment of FTIR wavenumbers (cm-1) for glycinium maleate

82

3.3 Assignment of FTIR wavenumbers (cm-1) for TGBDD 84

3.4 Comparison of FTIR wavenumbers (cm-1) of GT with corresponding values of glycine and thiourea

86

3.5 Assignment of FTIR wavenumbers for TCZC and TuTGZC 88

3.6 Comparison of FTIR wavenumbers (cm-1) of free ligand thiourea and other metal complexes

91

3.7 Comparison of FTIR wavenumbers (cm-1) of TPMS with thiourea, ZTS and MTS

93

3.8 Elemental analysis of the grown crystals 94

4.1 Mechanical parameters of the chosen compounds 118

5.1 Dielectric parameters of grown crystals at 10 KHz 139

6.1 Optical parameters of the grown crystals 155

6.2 Relative SHG efficiency of the grown crystals 157

6.3 Nonlinear optical parameters of the grown crystals 164

7.1 Results of growth, structural, thermal, mechanical and dielectric studies of the grown crystals

171

7.2 Results of linear and nonlinear optical studies of the grown crystals

172

vii

LIST OF FIGURES

Figure No.

Title Page No.

1.1 Plot of polarization of response 7 1.2 Second Harmonic generation 8 1.3 Parametric generation 8 1.4 Process of nucleation 30 1.5 Plot of Gibbs free energy change of nucleation 32 1.6 Growth of a crystal 33 2.1 Solubility curve of LVZA 60 2.2 Solubility curve of GM 60 2.3 Solubility curve of TGBDD 60 2.4 Solubility curve of GT 61 2.5 Solubility curve of TuTGZC 61 2.6 Solubility curve of BTSN 61 2.7 Solubility curve of TPMS 62 2.8 Photograph of as - grown crystal of LVZA 62 2.9 Photograph of as - grown crystal of GM 63 2.10 Photograph of as - grown crystal of TGBDD 64 2.11 Photograph of as - grown crystal of GT 64 2.12 Photograph of as - grown crystal of TuTGZC 65 2.13 Photograph of as - grown crystal of BTSN 66 2.14 Photograph of as - grown crystal of TPMS 66 2.15 Powder XRD spectrum of LVZA 72 2.16 Powder XRD spectrum of GM 73 2.17 Powder XRD spectrum of TGBDD 73 2.18 Powder XRD spectrum of GT 73 2.19 Powder XRD spectrum of TuTGZC 74 2.20 Powder XRD spectrum of BTSN 74 2.21 Powder XRD spectrum of TPMS 74 3.1 FTIR Spectrum of LVZA crystal 79 3.2 FTIR Spectrum of GM crystal 81 3.3 FTIR Spectrum of TGBDD crystal 83 3.4 FTIR Spectrum of GT crystal 85 3.5 FTIR Spectrum of TuTGZC crystal 87 3.6 FTIR Spectrum of BTSN crystal 90 3.7 FTIR Spectrum of TPMS crystal 91 4.1 TGA/DTA curves of LVZA 99

viii

4.2 DSC curve of LVZA 100 4.3 TGA/DTA curves of GM 101 4.4 DSC curve of GM 102 4.5 TGA/DTA curves of TGBDD 102 4.6 TGA/DTA curves of GT 104 4.7 DSC curve of GT 104 4.8 TGA/DTA curves of TuTGZC 105 4.9 TGA/DTA curves of BTSN 106 4.10 DSC curve of BTSN 107 4.11 TGA/DTA curves of TPMS 108 4.12 DSC curve of TPMS 109 4.13 Variation of Vickers constant with hardness number for

LVZA, GM, TGBDD & GT 113

4.14 log P versus log d 115 4.15 d2 versus dn of TuTGZC, BTSN & TPMS 117 4.16 d2 versus dn of LVZA & TGBDD 117 4.17 d2 versus dn of GM & GT 117 4.18 Variation of stiffness constant with hardness number for

LVZA, GM, TGBDD & GT 119

4.19 Variation of stiffness constant with hardness number for TuTGZC, BTSN & TPMS

119

4.20 Variation of yield strength with hardness number for LVZA, GM, TGBDD & GT

120

4.21 Variation of yield strength with hardness number for TuTGZC, BTSN & TPMS

120

5.1 Dielectric constant of all the compounds as a function of frequency at 35°C

133

5.2 Dielectric constant of all the compounds as a function of frequency at 45°C

133

5.3 Dielectric constant of all the compounds as a function of frequency at 55°C

133

5.4 Dielectric loss of all the compounds as a function of frequency at 35°C

137

5.5 Dielectric loss of all the compounds as a function of frequency at 45°C

137

5.6 Dielectric loss of all the compounds as a function of frequency at 55°C

137

5.7 Arrhenius plot for all the grown crystals: log (σT) versus 1000/T at 10 KHz

138

5.8 Frequency dependence of σac at 35°C 140

ix

5.9 Frequency dependence of σac at 45°C 140 5.10 Frequency dependence of σac at 55°C 140 5.11 Impedance (Z) of the grown crystals as a function of

frequency at 35°C 141

5.12 Impedance (Z) of the grown crystals as a function of frequency at 45°C

141

5.13 Impedance (Z) of the grown crystals as a function of frequency at 55°C

142

6.1 Transmittance pattern of the grown crystals 148 6.2 Absorbance pattern of the grown crystals 149 6.3 Reflectance pattern of the grown crystals 149 6.4 Energy diagram of all the crystals 151 6.5 Extinction coefficient as a function of photon energy of all

the crystals 153

6.6 Refractive index as a function of photon energy of all the crystals

153

6.7 Optical conductivity as a function of photon energy of all the crystals

154

6.8 Electrical conductivity as a function of photon energy of all the crystals

154

6.9 Experimental arrangement of powder SHG measurement 156 6.10 Experimental set up for Z-scan measurements 159

6.11(a) Z-scan pattern of LVZA, GM, TGBDD & GT - Closed Aperture (CA)

162

6.11(b) Z-scan pattern of LVZA, GM, TGBDD & GT - Open Aperture (OA)

162

6.11(c) Z-scan pattern of LVZA, GM, TGBDD & GT - Ratio of OA and CA

162

6.12(a) Z-scan pattern of TuTGZC, BTSN & TPMS - Open Aperture (OA)

163

6.12(b) Z-scan pattern of TuTGZC, BTSN & TPMS - Closed Aperture (CA)

163

6.12(c) Z-scan pattern of TuTGZC, BTSN & TPMS - Ratio of OA and CA

163

x

LIST OF PUBLICATIONS (In peer reviewed international journals)

[1] Growth and characterization of a new metal- organic nonlinear

optical thiourea potassium magnesium sulphate single crystals, A.

Ruby and S. Alfred Cecil Raj, Archives of Physics Research, 2012,

3(2): 130-137 (ISSN:0976-0970).

[2] Synthesis, growth, spectroscopic, optical and thermal studies of

Glycinium maleate single crystals, A. Ruby and S. Alfred Cecil Raj,

Advances in Applied Science Research, 2012, 3(3): 1677-1685

(ISSN:0976-8610).

[3] Synthesis, growth and characterization of Triglycine barium

dichloride dihydrate crystals, A. Ruby and S. Alfred Cecil Raj, World

Journal of Science and Technology, 2012, 2: 11-15 (ISSN: 2231-2587).

[4] Growth, spectral, optical and thermal characterization of NLO

organic crystal - Glycine Thiourea, A. Ruby and S. Alfred Cecil Raj,

International Journal of Chem. Tech Research, 2013, 5: 482-490

(ISSN: 0974- 4290).

[5] Growth, spectral, optical, thermal and mechanical properties of

doped Trisglycine zinc chloride nonlinear optical crystal, A. Ruby

and S. Alfred Cecil Raj, International Journal of Scientific and Research

Publications, 2013, 3, Issue 3: 1-5 (ISSN: 2250-3153).

[6] Synthesis, growth, spectral, optical and thermal studies of an organo

metallic single crystal - Bisthiourea Sodium Nitrate, A. Ruby and

S. Alfred Cecil Raj - Spectrochimica Acta Part A - Communicated.

[7] Growth and spectral characterization of L-Valine Zinc Acetate

single crystal, A. Ruby and S. Alfred Cecil Raj - Recent Research in

Science and Technology - Communicated.

xi

CONFERENCE PRESENTATIONS

[1] Growth and characterization of a novel metal organic nonlinear

optical crystal: Barium maleate, A. Ruby and S. Alfred Cecil Raj,

Proceedings of the 14th National Seminar on crystal growth (NSCG- XIV),

March 10 - 12, 2010, VIT University.

[2] Mechanical properties of thiourea complexes, A. Ruby, S. Alfred Cecil Raj

and J. Narmadha, Proceedings of the International conference on Advanced

Materials (ICAM 2012), page, 352-356, (ISBN No: 9788190949019),

January 5-7, 2012, Dept. of Physics, Loyola College, Chennai - 34.

xii

ABBREVIATIONS

NLO - Non Linear Optics

UV - Ultra Violet

TGA - Thermo Gravimetric Analysis

DTA - Differential Thermal Analysis

DSC - Differential Scanning Calorimetry

CHNS - Carbon Hydrogen Nitrogen Sulphur

FTIR - Fourier Transform Infra Red

XRD - X-ray Diffraction

NIR - Near Infra Red

SHG - Second Harmonic Generation

AC - Alternating Current

DC - Direct Current

SPM - Self Phase Modulation

XPM - Cross Phase Modulation

FWM - Four Wave Mixing

OPA - Optical Parametric Amplifiers

PCM - Phase Conjugate Mirrors

OPO - Optical Parametric Oscillator

AR - Analytical Reagent

CTB - Constant Temperature Bath

CPS - Cycles Per Second

CP - Heat capacity at constant pressure

Hv - Vickers Hardness

Eg - Energy gap

σop - Optical conductivity

σel - Electrical conductivity

esu - Electro Static Unit

SONLO - Second Order Non Linear Optical

TONLO - Third Order Non Linear Optical

xiii

SYMBOLS

V/cm - volt per centimetre

µm - Micrometre

ps - Picoseconds

nm - Nanometre

λ - wavelength

ω - frequency

pm/ V - Picometre per volt

W/ cmK - Watt per centimetre Kelvin

α - Alpha

β - Beta

γ - Gamma

°C - Degree Centigrade or Celsius

mm - Millimetre

Å - Angstrung unit

(°) - Degree

cm-1 - Per centimetre

mg - Milligram

J/g/ °C - Joules per gram per degree Celsius

kg - Kilogram

g - Gram

xiv

GPa - Gigga Pascal

MPa - Mega Pascal

s-1 - Per second

ε0 - Permittivity of free space

KHz - Kilo Hertz

Hz - Hertz

kB - Boltzmann constant

MΩ - Meg ohm

meV - Milli electron volt

JS - Joules second

kCal/mol - Kilocalorie per mole

ohm-cm - Ohm-centimetre

eV - Electron volt

ns - Nano second

mJ/p - Milli Joules per pulse

mV - Millivolt

cm/W - Centimetre per watt

xv

PREFACE

Crystals are the key materials of many solid state devices. Particularly

nonlinear optical (NLO) crystals are widely used in the field of photonics and

information technology. The growth of single crystal is a fundamental part of

Material Science and Engineering. Organic nonlinear materials play a key

functions in optical communication devices. Among organic materials, amino

acids exhibit wide transparency ranges in the UV-visible spectral regions and

their zwitterionic nature favours crystal hardness. Semi organic materials

attract a great deal of attention in the field of nonlinear optics due to their

excellent optical nonlinearity and thermal stability. The applications of NLO

crystals are based on various properties of materials such as transparency,

dielectric nature, refractive index, crystal hardness, thermal and chemical

stabilities.

Based on the literature survey, the research was carried out to

investigate the growth aspects and to explore the various properties of the

L-Valine, Glycine and thiourea based NLO crystals. The content of the thesis

are given into seven chapters.

Chapter - I gives the introduction to the field of nonlinear optics and

the nonlinear optical materials. It explains the various nonlinear optical effects

and the desirable properties for the NLO materials. Based on the wide

applications of NLO materials in the field of photonics and the literature

survey, it explains the learning objectives for the investigation of new nonlinear

optical materials and its various properties.

xvi

Chapter - II presents the details of low temperature solution growth. It

describes about the general scheme for growth of a crystal from solution and

description of the solution growth apparatus. It explains about the synthesis of

the materials such as LVZA, GM, TGBDD, GT, TuTGZC, BTSN and

TPMS. It gives details of solubility studies with different solvents, and crystal

growth. Solubility studies exhibited a positive temperature gradient and water

was found to be suitable solvent. Good optical quality bulk single crystals were

grown from aqueous solution by slow evaporation technique. Finally it

explains about single crystal and powder X-ray diffraction analysis of the

grown crystals. From X-ray diffraction studies it was found that the LVZA,

GM, GT, BTSN were crystallized in monoclinic system and TGBDD,

TuTGZC, TPMS crystallized in orthorhombic system.

Chapter - III explains the vibrational and elemental studies of the

grown crystals. This chapter covers FTIR spectral studies of the grown crystals.

FTIR spectral studies of all the grown crystals confirmed the presence of

functional groups in the compound. Amino acid crystals showed zwitterionic

nature and metal organic compounds of thiourea showed the metal ion

inclusion. The experimental CHNS values obtained were in good agreement

with the calculated values.

Chapter - IV describes thermal and mechanical properties of the grown

crystals. It explains the thermal stability of the grown crystals with TGA/DTA

and DSC analyses. From this analysis, melting point, major decomposition

xvii

temperature range and specific heat capacity of the materials were found. This

chapter also presents the details of Vickers microhardness measurements, the

calculations of mechanical parameters, such as Meyer’s index, material

resistance, stiffness constant and yield strength.

Chapter - V explains dielectric analysis of the grown crystals. It gives

the details of dielectric constant, dielectric loss, activation energy and

impedance with the variation of frequency and different temperature.

Chapter - VI describes linear and nonlinear optical properties of the

grown crystals. It covers optical properties such as transmittance, absorbance

and reflectance of all the grown crystals with UV-vis-NIR spectra.

Transparency window was found for all the crystals from UV-vis-NIR spectral

studies. The variation of optical parameters such as extinction coefficient,

refractive index, absorption coefficient, optical conductivity, electrical

conductivity and band gap with photon energy are explained. Investigated

relative SHG efficiency of all the compounds are given. The SHG efficiency of

the powdered samples was found relatively with KDP. The third order

nonlinear parameters such as nonlinear refractive index, nonlinear absorption

coefficient and third order susceptibilities were calculated.

Chapter - VII summarizes the results of the present investigation and

the scope of the future work.