Showing papers by "S. M. Dharmaprakash published in 2007"

Third order nonlinear optical properties and optical limiting in donor/acceptor substituted 4′-methoxy chalcone derivatives

Abstract: The third order nonlinear optical properties of 4′-methoxy chalcone and its derivatives have been investigated using a single-beam Z-scan technique with nanosecond laser pulses at 532 nm. The 4′-methoxy chalcone and its derivatives are donor–acceptor–acceptor (D–A–A) and donor–acceptor–donor (D–A–D) type intramolecular charge transfer molecules. The nonlinear response in these molecules was found to increase with increase in (a) the electron acceptor strength in D–A–A type and (b) the donor strength of the substituted group in D–A–D type molecules. The χ(3) value in these molecules is found to be of the order of 10-13 esu. The observed increase in the third order nonlinearity in these molecules clearly indicates the electronic origin. The compounds exhibit good optical limiting at 532 nm. The best optical limiting behavior was observed with the molecule substituted by a strong electron donor.

(2E,4E)‐1‐(3‐Nitrophenyl)‐5‐phenylpenta‐2,4‐dien‐1‐one

Abstract: In the title compound, C17H13NO3, the dihedral angle between the benzene rings is 2.57 (4)°. The crystal structure is stabilized by C—H⋯O inter­actions, which form a three-dimensional network, and by C—H⋯π inter­actions.

1-(4-Bromophenyl)-3-(3-methoxyphenyl)prop-2-en-1-one

Abstract: The title compound, C16H13BrO2, crystallizes with two independent mol­ecules (A and B) in the asymmetric unit. The dihedral angle between the two benzene rings is 45.94 (8)° in mol­ecule A and 46.82 (7)° in mol­ecule B. The crystal packing is stabilized by weak C—H⋯π inter­actions.

1‐(3‐Bromo­phen­yl)‐3‐[4‐(dimethyl­amino)phenyl]prop‐2‐en‐1‐one

Abstract: The title compound, C17H16BrNO, adopts an E configuration. The dihedral angle between the two benzene rings is 49.17 (13)°. Intra­molecular C—H⋯O weak inter­actions are present in the crystal structure. The mol­ecules are arranged in double layers parallel to the bc plane. These double layers are stacked in an anti-parallel fashion along the a axis. The crystal structure is stabilized by intra­molecular C—H⋯O weak inter­actions. C—H⋯π inter­action are also observed in the crystal packing.

3‐(5‐Bromo‐2‐thien­yl)‐1‐(4‐methoxy­phen­yl)prop‐2‐en‐1‐one

Abstract: The title compound, C13H8BrNO3S, crystallizes with two mol­ecules in the asymmetric unit. All bond lengths and angles in both mol­ecules show normal values. In the crystal structure, the mol­ecules are stabilized by inter­molecular C—H⋯O hydrogen bonds and short Br⋯O inter­actions.

Sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate

Abstract: The title compound, Na(+) x 3C(2)H(6)NO(2)(+) x 2SiF(6)(2-) x 3C(2)H(5)NO(2), arose from an unexpected reaction of glycine and HF with the glass container. It is an unusual hybrid organic-inorganic network built up from chains of vertex-sharing NaF(4)O(2) and SiF(6) octahedra. A pair of glycinium/glycine molecules bridges the chains into a sheet via a centrosymmetric O...H...O link. The other organic species interact with the network by an extensive N-H...F hydrogen-bond network, including bifurcated and trifurcated bonds. Finally, an extremely short C-H...O interaction (H...O = 2.25 Angstrom) is seen in the crystal structure. The Na atom has site symmetry overline1.

(2E)-3-[4-(Dimethylamino)phenyl]-1-(3-nitrophenyl)prop-2-en-1-one

Abstract: In the title compound, C17H16N2O3, the dihedral angle between the benzene rings is 1.56 (7)°. The nitro group is coplanar with the attached benzene ring while the dimethyl­amino group is twisted slightly away from the attached benzene ring. A weak intra­molecular C—H⋯O hydrogen bond is present in the mol­ecular structure. The crystal structure is stabilized by inter­molecular C—H⋯O hydrogen bonds, forming chains along the [011] direction.

(2E,2′E)‐1,1′‐Bis(4‐chlorophenyl)‐3,3′‐(1,4‐phenylene)diprop‐2‐en‐1‐one

Abstract: In the centrosymmetric title compound, C24H16Cl2O2, the dihedral angle between the central and terminal benzene rings is 4627 (9)° Edge-to-face C—H⋯π inter­actions are observed, with H⋯centroid distances in the range 270–283 A Cl⋯Cl contacts of 33701 (14) A are also present

1-(4-Bromophenyl)-3-(3-methyl-2-thienyl)prop-2-en-1-one

Abstract: The title compound, C14H11BrOS, crystallizes with four independent mol­ecules (A, B, C and D) in the asymmetric unit which differ in the orientations of the thio­phene and benzene rings with respect to the enone unit. The dihedral angles between the benzene and thio­phene rings are 6.03 (14), 21.79 (14), 15.04 (14) and 4.92 (14)°, respectively, in mol­ecules A, B, C and D. Intra­molecular C—H⋯O and C—H⋯S inter­actions generate S(5) ring motifs. In the crystal structure, weak C—H⋯O inter­molecular hydrogen bonds link the mol­ecules into layers parallel to the [011] plane. In addition, short inter­molecular Br⋯O contacts [2.997 (2)–3.110 (2) A] are observed.

1-(4-Hydroxyphenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one

Abstract: In the chalcone-derived title compound, C18H18O5, the dihedral angle between the aromatic ring mean planes is 16.64 (15)°. In the crystal structure, adjacent mol­ecules inter­act by way of O—H⋯O=C hydrogen bonds, leading to C(8) chains. A C—H⋯π inter­action also helps to stabilize the centrosymmetric crystal packing.

3-(4-Chloro­phen­yl)-1-(2-hydroxy­phen­yl)prop-2-en-1-one

Abstract: The title compound, C15H11ClO2, is almost planar and adopts an E configuration. The dihedral angle between the two benzene rings is 10.76 (6)°. An intra­molecular O—H⋯O hydrogen bond generates an S(6) ring motif. Mol­ecules are arranged in layers approximately parallel to the (204) plane and weak π–π inter­actions are observed between the layers.

(2E,2′E)-3,3′-(1,4-Phenylene)bis[1-(3,4-dimethoxyphenyl)prop-2-en-1-one]

Abstract: In the centrosymmetric title compound, C26H22O4, the dihedral angle between the central and terminal aromatic rings is 13.78 (12)°. A weak C—H⋯π inter­action may help to consolidate the crystal packing.

4-Meth­oxy-2-nitro­aniline

Abstract: The title mol­ecule, C7H8N2O3, lies on a mirror plane with two of the methyl H atoms related by mirror symmetry. The crystal structure is stabilized by inter­molecular N—H⋯O and C—H⋯O hydrogen bonds.

1‐(4‐Bromophenyl)‐3‐(2‐chloro‐6‐fluorophenyl)prop‐2‐en‐1‐one

Abstract: In the title mol­ecule, C15H9BrClFO, the dihedral angle between the two benzene rings is 22.7 (1)°. The crystal structure is stabilized by inter­molecular C—H⋯F inter­actions and short Br⋯Cl contacts [Br⋯Cl = 3.579 (1) A]. The compound can potentially exhibit second-order nonlinear optical properties as it crystallizes in a noncentrosymmetric space group.

(2E)-1-(3-Bromophenyl)-3-(4-chlorophenyl)prop-2-en-1-one

Abstract: In the title compound, C15H10BrClO, the dihedral angle between the benzene rings is 46.70 (5)°. The crystal structure is stabilized by Br⋯Br and Cl⋯Cl contacts and C—H⋯π inter­actions.

(E)-3-(4-Chloro-phen-yl)-1-(2,4-dichloro-5-fluoro-phen-yl)prop-2-en-1-one.

Abstract: In the title chalcone derivative, C15H8Cl3FO, the dihedral angle between the two benzene rings is 43.35 (8)°. Weak C—H⋯O and C—H⋯Cl intra­molecular inter­actions involving the enone group generate S(5) and S(6) ring motifs, respectively. In the crystal structure, mol­ecules are linked into anti­parallel chains along the a axis. These chains are stacked along the b axis and short Cl⋯F contacts of 3.100 (1) A link adjacent mol­ecules of the anti­parallel chains into dimers.

1,5‐Bis(3,4,5‐trimethoxyphenyl)penta‐1,4‐dien‐3‐one 1.333‐hydrate–1,5‐bis(3‐bromo‐4,5‐dimethoxyphenyl)penta‐1,4‐dien‐3‐one 1.333‐hydrate 0.919 (3):0.081 (3) cocrystal

Abstract: The title cocrystal, 0.919 (3)(C23H26O7·1.333H2O)·0.081 (3)(C22H20Br2O5·1.333H2O), arose due to the presence of an impurity in one of the starting materials. In both cases, the complete organic mol­ecule has twofold rotation symmetry, with the central C=O group lying on the rotation axis.

(2E)-1-{4-[(1E)-Benzylideneamino]-phenyl}-3-phenylprop-2-en-1-one

Abstract: In the title compound, C22H17NO, the dihedral angles between the central benzene ring and the two terminal phenyl rings are 48.20 (4) and 49.62 (4)°, resulting in a substanti­ally twisted mol­ecular conformation. Weak C—H⋯π inter­actions help to consolidate the centrosymmetric crystal packing.

1-(4-aminophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one-1-(4-aminophenyl)-3-(3-bromo-4,5-trimethoxyphenyl)prop-2-en-1-one (0.972/0.028)

Abstract: In the title cocrystal, 0.972(C18H19NO4).0.028(C17H16BrNO3), which arose from an impure starting material, all the atoms are overlapped except for one OMe group and the Br atom. The dihedral angle between the benzene ring mean planes is 18.20 (13)°. A weak N—H⋯O hydrogen bond helps to establish the non-centrosymmetric crystal packing.

(2E)-1-(3-Bromophenyl)-3-phenylprop-2-en-1-one

Abstract: In the title compound, C15H11BrO, the dihedral angle between the two benzene rings is 49.93 (8)°. The mol­ecules are arranged into infinite chains along the c axis through weak C—H⋯Br inter­actions. The chains are stacked along the a axis, forming layers.

3‐[(4‐Nitrophenyl)aminocarbonyl]propanoic acid

Abstract: The title compound, C10H10N2O5, crystallizes in the centrosymmetric space group P21/c. The carboxyl terminus end is almost perpendicular to the rest of the molecule [the dihedral angle between mean planes through the terminal COOH group, the adjacent C atom and rest of the molecule, except for the methylene H atoms, is 82.15 (18)°]. This molecule fails to show second-order nonlinear optical property due to the presence of inversion symmetry in the solid state. The crystal structure is stabilized by strong inter­molecular O—H⋯·O and N—H⋯·O hydrogen bonding.

3-(3-Methoxy­phen­yl)-1-(4-methoxy­phen­yl)prop-2-en-1-one

Abstract: In the title compound, C17H16O3, the dihedral angle between the benzene rings is 10.05 (9)°. Inter­molecular C—H⋯O hydrogen bonds link the mol­ecules to form chains along the b axis. The crystal structure is further stabilized by C—H⋯π inter­actions.

1,3-Bis(3,4-dimethoxyphenyl)prop-2-en-1-one

Abstract: In the title compound, C19H20O5, the dihedral angle between the benzene rings is 592 (6)° The mol­ecules are linked by two pairs of C—H⋯O hydrogen bonds into a centrosymmetric dimer of R21(6) ring motif In addition, the crystal structure is stabilized by C—H⋯π inter­actions