Odd-even Effect Research Articles

The effect of geometrical shape and molecular rigidity on mesomorphism

ABSTRACTA novel nonlinear homologous series RO‒C6H4‒CH˭CH‒COO‒C6H4 (meta) ‒CO‒CH˭CH‒C6H4‒OC12H25(n) (para) consisting of three phenyl rings, two central bridges ‒CH˭CH‒COO‒ and ‒CO‒CH˭CH‒ as well as ‒OR and ‒OC12H25(n) as flexible and constant terminal end groups respectively. The object in view is aimed to understand and establish the effect of molecular structure on LC properties of nonlinear inverted “V” shaped molecules. Novel homologous series consists of thirteen homologues. Transition temperatures and textures were determined by polarizing optical microscopy (POM) equipped with a heating stage. Textures of nematic phases are threaded or schlieren and that of a smectic phases are of the type-A or C. Transition curves of a phase diagram behaved in a normal manner. Sm-N and N-I transition curves exhibited odd-even effect. Analytical, Thermal and Spectral data confirms the molecular structure of homologues.

Study of mesomorphism dependence on molecular flexibility of an azoester series containing a napthyl unit

ABSTRACTA novel azoester homologous series of liquid crystalline (LC) compounds: RO‒C6H4-COO‒C10H6-N:N-C6H4‒OC4H9(n) without lateral substitution has been synthesized and studied with a view to understanding and establishing the effects of molecular structure on thermotropic LC substances with reference to tailed-end group. The novel homologous series consists of 13 homologs (C1 to C18) whose nematogenic and smectogenic mesomorphism commences enantiotropically from C6 and C12 members of the series, respectively. The C12–C18 homologs are smectogenic and C6–C18 are nematogenic, of which C12–C18 homologs are smectogenic plus nematogenic. The C1–C5 homologs are nonmesogenic. Transition temperatures and the textures of the homologs were determined and identified by an optical polarizing microscope (POM) equipped with a heating stage. Textures of a nematic phase are threaded or Schlieren and that of the smectic phase are of the type A or C. Transition curves Cr-M/I, Sm-N and N-I of a phase diagram behaved in normal manner except N-I transition temperature of C10 homolog which deviated by 9°C–10°C from normal behavior. N-I transition curve exhibited odd-even effect. Analytical, spectral, and thermal data confirms the molecular structures of homologs. Thermal stability for smectic and nematic are 115.5°C and 138.5°C, respectively whose corresponding mesophaselengths are varied from 10.0°C to 16.0°C and 13.0°C to 24.0°C, respectively. Group efficiency order for smectic and nematic are derived from comparative study of structurally similar analogous series; as smectic: ‒OC4H9 (n) > ‒CH3 > ‒H; Nematic: ‒H > ‒OC4H9 (n) > ‒CH3

Electronic and optical properties of boron and nitrogen pair co-doped 6,6,12-graphyne nanosheet

We investigate the electronic and optical properties of boron-nitrogen pair co-doped 6,6,12-graphyne nanosheets using first-principles calculations. For the electronic band structure, we find the band gap exhibits an even-odd effect with an increase in doping concentration. Exploring the optical properties, we calculate the dielectric function, reflectivity, and absorption coefficient under both parallel and perpendicular polarizations. Remarkably, the co-doped 6,6,12-graphyne shows a broad frequency photo-response. Under parallel polarizations, co-doping leads to a reduced static dielectric constant in the long wavelength limit. Furthermore, the reflectivity and absorption spectra show that the co-doped 6,6,12-graphyne nanosheets are highly sensitive to light from the infrared to the ultraviolet regimes. When doping concentration increases, the maximum reflectivity coefficient increases after an initial decrease under the longitudinal parallel polarization, in contrast to its oscillating behavior under the transverse parallel polarization. For all polarizations, the maximum absorption coefficient varies non-monotonically with doping concentration.

Even the Odd Numbers Help: Failure Modes of SAM-Based Tunnel Junctions Probed via Odd-Even Effects Revealed in Synchrotrons and Supercomputers.

This Account describes a body of research in atomic level design, synthesis, physicochemical characterization, and macroscopic electrical testing of molecular devices made from ferrocene-functionalized alkanethiol molecules, which are molecular diodes, with the aim to identify, and resolve, the failure modes that cause leakage currents. The mismatch in size between the ferrocene headgroup and alkane rod makes waxlike highly dynamic self-assembled monolayers (SAMs) on coinage metals that show remarkable atomic-scale sensitivity in their electrical properties. Our results make clear that molecular tunnel junction devices provide an excellent testbed to probe the electronic and supramolecular structures of SAMs on inorganic substrates. Contacting these SAMs to a eutectic "EGaIn" alloy top-electrode, we designed highly stable long-lived molecular switches of the form electrode-SAM-electrode with robust rectification ratios of up to 3 orders of magnitude. The graphic that accompanies this conspectus displays a computed SAM packing structure, illustrating the lollipop shape of the molecules that gives dynamic SAM supramolecular structures and also the molecule-electrode van der Waals (vdW) contacts that must be controlled to form good SAM-based devices. In this Account, we first trace the evolution of SAM-based electronic devices and rationalize their operation using energy level diagrams. We describe the measurement of device properties using near edge X-ray absorption fine structure spectroscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy complemented by molecular dynamics and electronic structure calculations together with large numbers of electrical measurements. We discuss how data obtained from these combined experimental/simulation codesign studies demonstrate control over the supramolecular and electronic structure of the devices, tuning odd-even effects to optimize inherent packing tendencies of the molecules in order to minimize leakage currents in the junctions. It is now possible, but still very costly to create atomically smooth electrodes and we discuss progress toward masking electrode imperfections using cooperative molecule-electrode contacts that are only accessible by dynamic SAM structures. Finally, the unique ability of SAM devices to achieve simultaneously high and atom-sensitive electrical switching is summarized and discussed. While putting these structures to work as real world electronic devices remains very challenging, we speculate on the scientific and technological advances that are required to further improve electronic and supramolecular structure, toward the creation of high yields of long-lived molecular devices with (very) large, reproducible rectification ratios.

Ground state phase transition in the Nilsson mean-field plus standard pairing model

The ground state phase transition in Nd, Sm, and Gd isotopes is investigated by using the Nilsson mean-field plus standard pairing model based on the exact solutions obtained from the extended Heine-Stieltjes correspondence. The results of the model calculations successfully reproduce the critical phenomena observed experimentally in the odd-even mass differences, odd-even differences of two-neutron separation energy, and the $\ensuremath{\alpha}$-decay and double ${\ensuremath{\beta}}^{\ensuremath{-}}$-decay energies of these isotopes. Since the odd-even effects are the most important signatures of pairing interactions in nuclei, the model calculations yield microscopic insight into the nature of the ground state phase transition manifested by the standard pairing interaction.

Empirical Evidence for Roughness-Dependent Limit in Observation of Odd-Even Effect in Wetting Properties of Polar Liquids on n-Alkanethiolate Self-Assembled Monolayers.

Substrate roughness influences the wetting properties of self-assembled monolayers (SAMs), but details on this dependency at the sub-nanometer level are still lacking. This study investigates the effect of surface roughness on interfacial properties of n-alkanethiolate SAMs, specifically wetting, and confirms the predicted limit to the observation of the odd-even effect in hydrophobicity. This article studies static contact angles of polar and nonpolar probe liquids on a series of n-alkanethiolate SAMs on surfaces with tunable roughness. We prepared Ag surfaces with root-mean-square roughness (Rrms) of ∼0.6-2.2 nm and compared the wetting properties of n-alkanethiolate SAMs fabricated on these surfaces. We measured the static contact angles, θs, formed between SAM and probe liquids [water, glycerol, and hexadecane]. Hexadecane showed an odd-even effect on all surfaces irrespective of the degree of roughness. Polar liquids (water and glycerol), however, showed a dependency on the roughness of the substrate with an odd-even effect observable only on smooth, but not rougher (Rrms ≥ 1.15 nm), surfaces. These results confirm that the previously predicted limit to observation of the odd-even effect in hydrophobicity (here extended to polar liquids) is real. From the results with glycerol, we infer that this limit is not limited just to hydrophobicity but may extend to other polar liquids. Results from hexadecane, however, suggest that this limit may not be a universal property of the SAM.

Thermally stable magnetic skyrmions in multilayer synthetic antiferromagnetic racetracks

A magnetic skyrmion is a topological magnetization structure with a nanometric size and a well-defined swirling spin distribution, which is anticipated to be an essential building block for novel skyrmion-based device applications. We study the motion of magnetic skyrmions in multilayer synthetic antiferromagnetic (SAF) racetracks as well as in conventional monolayer ferromagnetic (FM) racetracks at finite temperature. There is an odd-even effect of the constituent FM layer number on the skyrmion Hall effect (SkHE). Namely, due to the suppression of the SkHE, the magnetic skyrmion has no transverse motion in multilayer SAF racetracks packed with even FM layers. It is shown that a moving magnetic skyrmion is stable even at room temperature ($T=300$ K) in a bilayer SAF racetrack but it is destructed at $T=100$ K in a monolayer FM racetrack. Our results indicate that the SAF structures are reliable and promising candidates for future applications in skyrmion-electronics and skyrmion-spintronics.

Dependence of thermotropic mesomorphism on lateral nitro group

ABSTRACTA novel homologous series RO-C6H4-COO-C6H3-(NO2)-CO-CH˭CH-C6H4OC18H37(n) para of chalconyl ester derivatives have been synthesized and studied with view to understanding the effect of an ortho substituted nitro group on thermotropic liquid crystal (LC) behavior. The novel homologous series consists of thirteen homologues (C1 to C18). The C1 to C4 homologues are nonliquid crystal (NLC) and the rest of the homologues (C5 to C18) homologues are enantiotropically nematogenic without exhibition of a smectic phase even in the monotropic condition. Transition temperatures were determined by an optical polarizing microscope (POM) equipped with a heating stage. Texture of nematic phase are threaded or Schlieren. Analytical, thermal and spectral data supported molecular structure of homologues. Thermal stability for nematic is 147.1°C whose mesophase lengths vary between 16.0 and 32.0°C the C7 and C18 homologues, respectively, and their mesogenic exhibition range between 96.0 and 166.0°C. Thus, the present novel series is middle ordered melting type, Group efficiency order is derived from comparative study of structurally similar series. The transition curves of a phase diagram behaved in normal manner except C10 and C16 homologues. Odd-even effect is observed for N-I transition curve. Group efficiency order derived is: -OC12H25 (n) > -OC18H37 (n) > -OC18H37 (n).

Mesomorphism dependence of a terminal or lateral alkoxy group

ABSTRACTA novel homologous series of thermotropic mesomorphs has been synthesized and studied with a view to understanding and establishing the effect of molecular structure on mesomorphic properties with reference to rigidity and flexibility of the homologues series: RO-C6H4-CH˭CH-CO-C6H4-OC18H37(n). The novel homologous series comprises 13 novel homologues (C1 to C18), from which 11 homologues are enantiotropically mesogenic (C3 to C18). Smectogenic mesophase commences from C7 homologue, and nematogenic mesophase is exhibited by C3 to C18 homologues in enantiotropic manner. Thus, C7 to C18 homologues are enantiotropically smectogenic plus nematogenic. Textures of smectic phase are of the type A or C, and that of nematic phase are threaded or Schlieren as confirmed through an optical polarizing microscope equipped with a heating stage. Transition curve of a phase diagram behaved in a normal manner except N-I transition curve, which shows minor deviating trend (C12 to C18) from expected normal behavior. An odd-even effect is exhibited by N-I and Sm-N transition curves. Analytical, spectral, and thermal data confirm the molecular structures of novel homologues. Thermal stabilities for smectic and nematic are 52.7°C and 66.6°C, respectively, whose total mesophase lengths range from 12.0°C to 28.0°C. Thus, novel series of chalcones is a low melting series whose mesogenic transition temperatures vary between 38.0 and 86.0°C.

Study of mesomorphism and laterally substituted nitro group

ABSTRACTA novel thermotropically mesomorphic, meta-substituted nitro group of chalconyl ester series, RO-C6H4-COO-C6H3-(NO2)-CO-CH=CH-C6H4OC12H25(n) (para) is synthesized and studied with an aim to establish the relation between molecular structure and the mesomorphism with reference to changing molecular flexibility in presence of nitro lateral group. Novel homologous series consist of thirteen homologs (C1–C18) whose mesomorphism commences from C5 homolog as enantiotropic nematogenic with absence of smectic property, even in the monotropic condition. Transition temperatures of novel substances were determined by an optical polarizing microscope, equipped with a heating stage (POM). Textures of a nematic phase are threaded or Schlieren. N-I transition curve exhibited narrow, sharp and short odd-even effect; with deviating trend in a phase diagram. Analytical, spectral and thermal data confirmed the molecular structures of homologs. Thermal stability for nematic is 182.89°C, whose mesophase lengths minimum to maximum ranges from 17°C to 45°C and it is an upper middle ordered melting type series. Group efficiency order for nematic is series 1 > series Y > series X, as derived from comparative study of structurally similar analogous series.

Synthesis and mesomorphic behavior of liquid crystal chalconyl esters

ABSTRACTA chalconyl homologous novel series of thermotropic liquid crystals (LC) have been synthesized and studied with a view to understand and establish the effects of molecular structure on LC properties in thermotropic behaviors. Homologous series consists of 13 homologs (C1–C18), C1–C4 homologs are nonliquid crystals and the rest of the homologs are enantiotropically nematogenic without exhibition of smectic property. Transition temperatures and the textures of the nematic phase were determined by an optical polarizing microscopy, equipped with a heating stage (POM). Texture of a nematic phase are threaded or Schlieren. The Spectral and analytical data confirms the molecular structures of homologs. Cr-N/I and N-I transition curves behaved in normal manner except C7 homolog which shows negligible abnormality for N-I transition temperature or curve with exhibition of odd-even effect.

Role of n-alkoxy terminal end groups on mesomorphism

ABSTRACTA homologous series RO-C6H4-CH:CH-COO-C6H4-CO-CH:CH-C6H4-OC6H13 (n) of novel liquid crystals (LC) has been synthesized and studied with a view to understanding and establishing the relation between molecular structure of a substance and the LC properties or behavior of thermotropic LC materials. Novel series consist of 11 homologues. C1 and C2 homologue derivatives are non-LCs and the rest of homologues (C3 to C16) are nematogenic without exhibition of smectic property. Transition temperatures were determined by an optical polarizing microscopy equipped with a heating stage. Transition curve Cr-N/I of a phase diagram behaved in normal manner. N/I transition curve partly deviated at C6 and C10 homologues from normal descending behavior, and exhibited very narrow and sharp odd-even effects. Textures of nematic phase are threaded or Schlieren. Thermal, analytical, and spectral data confirmed the molecular structures of novel chalconyl ester derivatives. Thermal stability for nematic is 95.77°C and the upper and lower mesophase lengths vary from 35 to 16°C at C5 and C8 homologues respectively. Group efficiency order derived for nematic on the basis thermal stability is -OC10H21 (n) > -OC8H17(n) > -OC6H13(n).

Dependence of mesomorphism on molecular rigidity of nonlinear and linear isomeric and nonisomeric chalconyl esters

ABSTRACTThe novel thermotropic liquid crystalline (LC) materials have been synthesized and studied through chalconyl ester nonlinear (meta substituted) homologous series RO-C6H4‒CH˭CH‒COO‒C6H4-CO‒CH˭CH‒C6H4-OC14H29(n) with a view to understand the effect of molecular structure on LC behavior with reference to determine the difference between linear and nonlinear shaped molecules. Novel series consisted of thirteen members, whose nematogenic enantiotropic mesomorphism commences from C6 homologue and continued up to C18 homologue with the absence of smectogenic character. C1 to C5 homologues are nonliquid crystals as determined through an optical polarising microscope (POM) equipped with a heating stage. Transition temperatures of LC homologues alternate and are lower than the corresponding n-alkoxy cinnamic acids. Cr-N/I and N-I transition curve behaved in normal manner. N-I transition curve exhibited odd-even effect in a phase diagram. Textures of nematic phase are threaded or Schlieren or determined by miscibility method and from observing mesophase on the top of the POM. Thermal stability for nematic is 92.5 and mesophase length minimum to maximum is 19.0 to 32.0°C at the C10/18and C6 homologue. Group efficiency order on the basis of thermal stability is Thus, novel series is nematogenic and low melting type. Analytical and spectral data confirmed the molecular structures of homologues.

Mesomorphism dependence on halogenated chalconyl esters in terms of molecular flexibility/rigidity

ABSTRACTVinyl carboxy central group containing a novel chalconyl ester homologous series: RO.C6H4.CH ˭ CH.COO.C6H4.CH ˭ CH.CO.C6H4.I (para) have been synthesized and studied with a view to understand and establish the relation between thermotropic liquid crystalline (LC) behaviors and the molecular structure. Novel chalconyl ester homologous series consists of thirteen homologs (C1–C18). C1–C3 homologs are nonmesogenic, C4 homolog is enantiotropic nematogenic and the rest of the homologs (C5–C18) are enantiotropically smectogenic plus nematogenic. Phase transition temperatures and textures of LC phase were determined by an optical polarizing microscopy (POM) equipped with a heating stage. Cr-M/I, Sm-N, N-I transition curves in a phase diagram behaved in normal manner. Sm-N and N-I transition curves exhibited odd-even effect from C4–C10 or nearby C10 homolog. Textures of nematic phase are threaded or Schlieren and that of the smectic phase are of the type smectic A or C. Analytical and spectral data confirms the molecular structure of homologs. Thermal stabilities for smectic and nematic mesophases are 155.0 and 180.7, respectively, and their corresponding mesophaselengths are varied from minimum to maximum at 17.0°C–39.0°C as well as 15.0°C–30.0°C. Thus, it is middle ordered melting type series. The group efficiency orders derived on the basis of smectic and nematic thermal stabilities are as under: Sm: -C6H4.I > -C6H4.Cl > -C4H3S and N:- C6H4.I > -C6H4.Cl > -C4H3S from comparative study of structurally similar analogous series

Fragmentation cross section of 800 A · MeV silicon ions on polyethylene target

The total charge-changing cross sections and the partial cross sections of projectile fragment production of the fragmentation of silicon ions on polyethylene target at 800 A · MeV are measured using CR-39 plastic nuclear track detector. The total charge-changing cross sections of silicon ions on polyethylene targets at 800 A · MeV is 761 ± 24 mb, which agree well with the prediction of Bradt-Peters semi-empirical formula using parameter r0 = 1.31fm and b = 0.94 within experimental errors. The obvious even-odd effect is observed for the partial cross sections in present investigation.

Parity effect in a mesoscopic Fermi gas

We develop a quantitative analytic theory that accurately describes the odd-even effect observed experimentally in a one-dimensional, trapped Fermi gas with a small number of particles [G. Z\"urn et al., Phys. Rev. Lett. 111, 175302 (2013)]. We find that the underlying physics is similar to the parity effect known to exist in ultrasmall mesoscopic superconducting grains and atomic nuclei. However, in contrast to superconducting nanograins, the density (Hartree) correction dominates over the superconducting pairing fluctuations and leads to a much more pronounced odd-even effect in the mesoscopic, trapped Fermi gas. We calculate the corresponding parity parameter and separation energy using both perturbation theory and a path integral framework in the mesoscopic limit, generalized to account for the effects of the trap, pairing fluctuations, and Hartree corrections. Our results are in an excellent quantitative agreement with experimental data and exact diagonalization. Finally, we discuss a few-to-many particle crossover between the perturbative mesoscopic regime and non-perturbative many-body physics that the system approaches in the thermodynamic limit.

Particular aspects related to the even-odd effects in prompt emission

The present paper focuses on several particular aspects related to the even-odd effects in prompt emission in fission synthesized as follows: 1) The even-odd effects in prompt emission are the result of two contributions, a dominant one due to the even-odd nuclear character of fission fragments reflected in their properties and consequently in the emitted prompt neutrons and gammas, and a weaker contribution brought by the even-odd effect in the fragment distribution (over which the prompt emission matrices are averaged). Oscillations with a periodicity of about 5 mass units are present in different prompt emission quantities corresponding to even-Z and odd-Z fragmentations independent of the size of the even-odd effect in the charge yield Y(Z) . 2) The oscillation periodicity \(\Delta A\approx 5\) in the charge polarization \(\Delta Z(A)\) and rms(A) of the isobaric charge distribution as well as in the fragment mass yields Y(A) of even-Z and odd-Z fragmentations is also due to the periodicity of nuclear properties being independent of the size of the even-odd effect in Y(Z) . Only the magnitude of the oscillation amplitudes of \(\Delta Z(A)\) , rms(A) and Y(A) of even-Z and odd-Z fragmentations reflects in different ways the size of the even-odd effect in Y(Z) . 3) Not only the basic features of the global even-odd effect in fragment yields and prompt emission are the same but also the local even-odd effect in prompt emission --reported for the first time in this paper-- exhibits the same behaviour as the experimental data of the local even-odd effect in Y(Z) . 4) A correlation between the even-odd effect in Y(Z) and prompt emission quantities (e.g., \(\nu(Z)\) exists. This interrelation is through the nuclear properties of the fission fragments. The presence of oscillations with a period \(\Delta A\approx 5\) in both Y(A) and prompt emission quantities corresponding to even-Z and odd-Z fragmentations cannot be directly linked to the size of the even-odd effect in Y(Z) .

Contrasting Effects of a Rigid Core and an Alkyl Chain in nCB on the Phase Behavior of Lipid Bilayers.

Molecules incorporated into biomembranes often bear both a core and an alkyl chain in a single molecule (e.g., sterols). To clarify the effects of these two parts of a molecule, the phase behavior of a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayer containing 4-n-alkyl-4'-cyanobiphenyl (nCB) (n = 0-8) was investigated. The trends of the main transition temperature (Tm) with respect to n and of the pretransition temperature (Tp) with respect to nCB content changed at n = 3. It was therefore suggested that the two parts of the molecule had opposing effects on the phase behavior of DPPC bilayers. The core appears to perturb molecular ordering in the gel phase and lowers Tm (like cholesterol), while alkyl chains appear to order the lipids in the gel phase and raise Tm (like n-alkanes). In addition, Tm exhibits the so-called odd-even effect based on the alkyl chain length of the minor component, nCB. Depending on the value of n, the variation in Tp was dependent on the additive content, although the pretransition was rarely observed at high contents.

Synthesis and cytotoxic activity of novel 11-methyl-6H-pyrido[4,3-b]carbazole derivatives linked to amine, N-methylurea, and N-methyl-N-nitrosourea moieties with various types of carbamoyl tethers at the C-5 atom

Thirty-five types of novel pyridocarbazoles (5-(N-alkyl)carbamoyl-11-methyl-6H-pyrido[4,3-b]carbazoles and 5-(N-alkyl)carbamoyl-2,11-dimethyl-6H-pyrido[4,3-b]carbazol-2-ium chloride derivatives), that were conjugated with amine, N-methylurea, and N-methyl-N-nitrosourea moieties through alkyl-, oxyalkyl-, and iminoalkylcarbamoyl linkers, were synthesized by a series of reactions of methyl 11-methyl-6H-pyrido[4,3-b]carbazole-5-carboxylates with polymethylenediamine (n=2–5), p-nitrophenyl N-methylcarbamate, and N-methyl-N-nitrosocarbamate in high yields, and their cytotoxic activities were evaluated against Sarcoma-180, NIH3T3, HeLa S-3, and L1210 cell lines. These compounds exhibited potent cytotoxic activity (IC50=1.6–50 μM) and odd-even alternation effect. 9-Methoxy-2,11-dimethyl-5-((2-(3-methyl-3-nitrosoureido)ethyl)carbamoyl)-6H-pyrido[4,3-b]carbazol-2-ium chloride exhibited the most potent cytotoxic activity (IC50=0.15 μM) and cell selectivity against HeLa S-3. Some of the un-charged 5-(N-alkyl)carbamoyl-6H-pyrido[4,3-b]carbazole derivatives, which were conjugated with the amine and N-methyl-N-nitrosourea moieties through a dimethylene spacer, also exhibited potent cytotoxic activity (IC50=0.43–2.4 μM) and remarkable cell selectivity as well as ellipticine, 9-hydroxyellipticine, and the starting methyl ester of the pyridocarbazole-5-carboxylate (IC50=0.30–2.2 μM).

Dependence of thermotropic mesomorphism on molecular flexibility of changing tail group

ABSTRACTA novel chalconyl ester homologous series of liquid crystals has been synthesized and studied with a view to understanding and establishing the effect of molecular structure on liquid crystalline properties. Novel series consisted of 13 members (C1–C18) of a series. C1–C4 member of a series is nonliquid crystals and, the rest of the homolog members (C5–C18) are enantiotropically nematogenic with absence of smectogenic property. None of the homolog is monotropically mesomorphic. Transition and melting temperatures were determined by an optical microscope equipped with a heating stage. Textures of nematic phase are threaded or schlieren. Spectral and analytical data of selected members of a series confirms the molecular structures of homologues. Cr-N and N-I transition curves of a phase diagram behaved in normal manner with exhibition of odd-even effect of very short range as observed for N-I transition curve. Thermal stability for nematic is 122.0°C and the nematogenic mesophase ranges from 7.0°C to 38.0°C. Liquid crystal properties of a present series are compared with the structurally similar known homologous series.