• Journal of Photoscience
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• v.12 no.2
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• pp.101-107
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• 2005

Infrared multiphoton dissociation of $CHCl_2F$ was studied using $CO_2$ laser excitation. Three products, $C_2Cl_2F_2$, $C_2ClF_3$, and $C_2HClF_2$, were identified by the analysis of the gas mixture from the photoreaction of $CHCl_2F$. The dependence of the reaction probability on added Ar gas pressure and excitation laser pulse energy was investigated. At low pressure (< 10 torr), the reaction probability increased as Ar pressure increased due to the rotational hole-filling effect, while it diminished with the increase of Ar pressure at high pressure (> > 20 torr) due to the collisional deactivation. The ratio of two products $(C_2ClF_3/C_2Cl_2F_2)$ decreased at low pressure (< 10 torr) and increased at high pressure (> 20 torr) with the increase of Ar pressure. The log-log plot of the reaction probability vs. laser pulse energy (${\\phi}$) was found to have a linear relationship, and its slope decreased as the added Ar pressure was increased. The reaction mechanisms for product formation have been suggested and validated by experimental evidences and considering the energetics. Fluorine-chlorine exchange reaction in the intermediate complex has been suggested to explain the formation of $C_2ClF_3$.

• Korean Journal of Crystallography
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• v.7 no.2
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• pp.113-119
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• 1996

Reaction of Re(O)(PPh3)2Cl3,I, with 2,3,4,5,6-pentafluoroaniline (C6F5NH2), produced Re(NC6F5)(PPh3)2Cl3, II. The product has been characterized by 1H-NMR, elemental analysis, and X-ray diffraction. II crystallizes in the orthorhombic system, space group Pna21 with cell parameters a=18.763Å, b=14.737(2)Å, c=16.707(3)Å, Z=4. Least-square refinement of the structure led to an R(wR2)factor of 0.0455(0.1148) for 3319 unique reflections of I > 2σ(I) and for 174 variables.

• Journal of the Korean Chemical Society
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• v.11 no.3
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• pp.89-93
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• 1967

The interactions of fluorobenzene with iodine monochloride, iodine monobromide, bromine and chlorine in carbon tetrachloride solution have been examined through ultraviolet spectrophotometric measurements. The results indicate the formation of one to one molecular complexes, $C_6H_5F{\cdot}ICl$, $C_6H_5F{\cdot}IBr$, $C_6H_5F{\cdot}Br_2$, and $C_6H_5F{\cdot}Cl_2$ in solution. The equilibrium constants obtained at room temperature for the formation of these four complexes are 0.161, 0.072, 0.045 and 0.035 l $mole^{-1}$, respectively. Comparison of these results with those reported in the literature on other complexes of similar type reveals that the relative stabilities of these complexes decrease in the following orders: ICl>IBr>$I_2$>$Br_2$>$Cl_2$ $C_6H_6$>$C_6H_5Br$>$C_6H_5Cl$>$C_6H_5F$

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.339-350
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• 2004

The simplified cumulant method was applied to diffraction data of $CClF_3$ to study the equilibrium molecular parameters over a range of temperatures. The molecular parameters of $CClF_3$ by the simplified cumulant method were compared with those from the traditional method. Also the instrumentation of picosecond time resolved electron diffraction (TRED) and the experimental details are described. The total experimental temporal resolution was discussed in terms of the electron pulse width. The TRED system was applied to study the molecular structures for $CClF_3$ at room temperature. The molecular structural parameters $CClF_3$ from TRED are compared with those from GED/RT. The molecular parameters ($r_e$)of bonded C-F and C-Cl for $CClF_3$ by simplified CA are 132.00(2) pm and 175.20(3) pm, respectively, by using GED/RT. From the results of TRED experiments $r_a$ for bonded C-F and C-Cl are 132.23(13) pm and 177.23(19) pm.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.248-254
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• 1992

Bis(phosphine)ruthenium derivatives $({\eta}^5-C_5Me_5)RuCl(PR_3)_2(PR_3=PMe_3,\; PMe_2Ph,\;PEt_3,\;PMePh_2$, 1/2DPPE, 1/2DPPB) (2a${\sim}$2f) have been synthesized by the reaction of $[({\eta}^5-C_5Me_5)RuCl_2]_2$ (1) with excessive phosphine in ethanol. The reaction of complexes $({\eta}^5-C_5Me_5)Ru(PR_3)_2Cl\;with\;NaBH_4$ in ethanol gave the corresponding hydride complexes $({\eta}^5-C_5Me_5)Ru(PR_3)_2H (PR_3=PMe_3, PEt_3, PMePh_2$, 1/2 DPPE, 1/2DPPB) (3a${\sim}$3e). Chloride complexes (2a${\sim}$2f) and hydride complexes (3a${\sim}$3e) were isolated as crystals, which were characterized by IR, $^1H-NMR$ , and elemental analysis.

• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.131-140
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• 1993

To study the corrosion fatigue begavior of T.M.C.P. steel, the rotary bending fatigue test with the change of concentration of NaCl solution was carried out. Fatigue life in the corrosion environment is decreased markedly in comparision with that in the air. Fatigue limit in the air was about 225 MPa. In case of 3.5% NaCl solution fatigue life could be expressed as .sigma./sub f/=10,392 * (N/sub f/)/sup -o.2923 . According to the paris's rule, crack growth rates could be expressed as da/dN=2.62.*10/sup -7/ .DELTA. K/sup 1.09/(3.5% NaCl solution), da/dN=1.95 *10/sup -7 .DELTA. K/sup 1.05/(1% NaCl solution), da/dN=2.62 * 10/sup -7/.DELTA./sup 0.72/(0.01% NaCl solution) with da/dN expressed in mm/cycle and .DELTA.K in MPa.GAMMA.m. The crack growth rate in the corrosion environment was highest under 3.5% NaCl solution.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.213-216
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• 2001

Etching behaviors of ferroelectric YMn $O_3$ thin films were studied by an inductively coupled plasma (ICP). Etch characteristic on ferroelectric YMn $O_3$ thin film have been investigated in terms of etch rate, selectivity and etch profile. The maximum etch rate of YMn $O_3$ thin film is 300 $\AA$/min at Ar/C $l_2$ of 2/8, RF power of 800W, dc bias voltage of 200V, chamber pressure of 15mTorr and substrate temperature of 3$0^{\circ}C$. Addition of C $F_4$ gas decrease the etch rate of YMn $O_3$ thin film. From the results of XPS analysis, Y $F_{X}$ compunds were found on the surface of YMn $O_3$ thin film which is etched in Ar/C1/C $F_4$ plasma. The etch profile of YMn $O_3$ film is improved by addition of C $F_4$ gas into the Ar/C $l_2$ plasma. These results suggest that fluoride yttrium acts as a sidewall passivants which reduce the sticking coefficient of chlorine on YMn $O_3$.>.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.108-114
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• 1980

By using electrostatic model and simple bond additivity scheme a reasonable and simple method was developed for the estimation of standard enthalpy of formation $({\Delta}H_f\;^{\circ})$ of very polar compounds. The bond contributions to the enthalpy of formation for halomethanes were; ${\Delta}H_f\;^{\circ}(C-F)=-36.44\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-Cl)=-2.57\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-Br)=5.32\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-I)=19.18\;kcal/mole,\;and\;{\Delta}H_f\;^{\circ}(C-H)=-3.61\;kcal/mole$, respectively. Using these values and calculated electrostatic energies, the estimated ${\Delta}H_f\;^{\circ}$ values were estimated and found to be in good agreement with observed values.

• Journal of the Korean Chemical Society
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• v.7 no.3
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• pp.189-196
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• 1963

Reactions between potassium fluoride with organic halogen-containing carboxylic acids in dimethyl formamide solvent gave a decarboxylation reaction for the case of fluoro carboxylic acids of the type of $CF_3\;COOH,\;C_3F_7COOH,\;and\;C_2F_5COOH,$ whereas an additional partial fluorination together with dimerization reaction occurred for the chlorine containing acids of the type of $CH_2ClCOOH,\;CH_3CHClCOOH, \;CHCl_2COOH\;and\;o-Cl-C_6H_4-COOH.$ The phenyl halides showed no reactivity, but the halides with two electron attracting substituents on the benzene ring gave mainly dimerization reaction. The esters and alcohols gave an usual fluorination reaction. The same reactions in absence of the solvent at the elevated temperature increase the yield of the dimerized product and gave the cyclized product, fluorenone, in case of ο-chlorobenzoic acid. It was found that the fluorination usually precede the decarboxylation reaction by checking the stiochemical sequence of reaction. Catalytic influence of potassium fluoride were discussed and the mechanism of the reaction was considered.

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.184-189
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• 1998

Tris(pentafluorophenyl)indium acetonitrile complexes have been prepared from the reaction of Indium trihalides (halogen=Cl, Br) and bis(pentafluorophenyl)cadmium in acetonitrile, and characterized by elementary analysis, $^13C{^1H}-,\; ^1H-\;and\; ^{19}F-NMR$ spectroscopy and mass spectrometry. The Indium (III) compounds were formed stable 1:1 adducts with acetonitrile. $In(C_6F_5)_3{\cdot}DMAP$ has been prepared from the ligand exchange reaction of In$(C_6F_5)_3 {\cdot} CH_3CN$ with DMAP in $CH_2Cl_2 {\cdot} DMAP$ has higher donating character and replaced the $CH_3CN$ through the ligand transfer reaction.