Keiko Nishikawa
Emeritus Professor, Chiba University[Present Position]
Research Fellow at Toyota Physical and Chemical Research Institute[Research Field]
Physical Chemistry, Structural Chemistry of Disordered Materials, Condensed Matter Physics[Date of Birth]
November 27, 1948
[Sex] Female[Nationality] Japan[Academic Background]Mar. 1972 Faculty of Science, Department of Chemistry, The University of Tokyo
Mar. 1974 Graduate School of Science, Department of Chemistry, Master Course,
The University of Tokyo
Mar. 1981 Doctor of Science (The University of Tokyo)(Thesis Title: The Construction of Energy-Dispersive X-Ray Diffractometer for
Liquids and Structure of Liquids)[Professional Career]Aug. 1974−Mar. 1991 Assistant Professor, Faculty of Science, Gakushyuin University
Apr. 1991−Mar. 1996 Associate Professor, Faculty of Education, Yokohama National University
Apr. 1996−Mar. 2014 Professor, Graduate School of National Science, Chiba University
Jun.2014−Mar. 2018 Research Professor, Chiba University
Jun. 2014

Emeritus Professor, Chiba University

Apr. 2014−Aug. 2018 Inspector General, Japan Society for the Promotion of Science (JSPS)
Apr. 2018−Present

Research Fellow, Toyota Physical and Chemical Research Institute[Membership]
Chemical Society of Japan, Physical Society of Japan, Japan Society for Molecular Science,
The Crystallographic Society of Japan, The Japanese Society for Synchrotron Research, Ionic
Liquid Research Association

[Honors and Awards]
1988

CrSJ (The Crystallographic Society of Japan) Award

1998

Saruhashi Prize from “the Association for the Bright Future of Woman Scientists”

2012

CSJ (Chemistry Society of Japan) Award

2012

Commendation for Science and Technology by the Minister of Education, Culture,
Sports, Science and Technology

2013
2014

Medal with Purple Ribbon from Government of Japan
Award of Japan Society for Molecular SciencePublication List (2019)
Keiko Nishikawa

I. Original papers
1) Structure of Polyvanadotungstates I. The Crystal Structure of α-(CＮ ３ H ６ ) ４ V ２ W ４ O １９ .
K. Nishikawa, A. Kobayashi and Y. Sasaki
Bull. Chem. Soc. Jpn., 48, 889 (1975).
2) Structure of Polyvanadotungstates II. The Crystal Structure of K ７ V ５ W ８ O ４０ ．12H ２ O.
K. Nishikawa, A. Kobayashi and Y. Sasaki
Bull. Chem. Soc. Jpn., 48, 3152 (1975).
3) The Construction of Energy-Dispersive X-ray Diffractometer for Liquids and Its application to CCl 4 .
Y. Murata and K. Nishikawa
Bull. Chem. Soc. Jpn., 51, 411 (1978).
4) Liquids Structure of CCl 4 and Long-Range Correlation.
K. Nishikawa and Y. Murata
Bull. Chem. Soc. Jpn., 52, 293 (1979).
5) The Temperature Dependence of the Liquid Structure of CCl .
K. Nishikawa, K. Tohji, M. Shima and Y. Murata
Chem. Phys. Lett., 64, 154 (1979).
6) Direct Obsevation of Phase Transformation Process by Energy-Dispersive X-ray Diffractometry.
K. Tohji, K. Nishikawa and Y. Murata
Jpn. J. Appl. Phys., 19, L365 (1980).
7) X-ray Diffraction Study of Liquid Water.
K. Nishikawa and N. Kitagawa
Bull. Chem. Soc. Jpn., 53, 2804 (1980).
8) X-ray Diffraction Study of Liquid Methanol.
M. Tanaka, K. Nishikawa and T. Fujiyama
Chem. Lett., 327 (1981).
9) The Intermolecular Arrangement in Plastic Crystal (Phase Ia) of Carbon Tetrachloride Studied by
X-ray Diffraction.
K. Nishikawa, K. Tohji and Y. Murata
J. Chem. Phys., 74, 5817 (1981).
10) X-ray Diffraction Study of Mixing State in the Carbon Tetrachloride Solutions of Methanol andPentane.
M. Tanaka, K. Nishikawa, K. Tohji and T. Fujiyama
Bull. Chem. Soc. Jpn., 56, 1273 (1983).
11) Correction for Intensity Data in Energy-Dispersive X-ray Diffractometry of Liquids. Application to
Carbon Tetrachloride.
K. Nishikawa and T. Iijima
Bull. Chem. Soc. Jpn., 57, 1750 (1984).
12) Clathrate-like Structure of Water around Some Nonelectrolytes in Dilute Solution as Revealed byComputer Simulation and X-ray Diffraction Studies.
H. Tanaka, K. Nishikawa and K. Nakanishi
J. Inclusion Studies, 2, 119 (1984).

13) Structure Model for Liquid Carbon Tetrachloride.
K. Nishikawa and T. Iijima
Bull. Chem. Soc. Jpn., 58, 1215 (1985).
14) Mean Square Deviations of Interatomic Distances in Liquid Carbon Tetrachloride.
K. Nishikawa and T. Iijima
Bull. Chem. Soc Jpn., 58, 1220 (1985).
15) Use of Reciprocal Space Expansion in the Analysis of X-ray Scattering Intensities from Liquids.
T. Iijima and K. Nishikawa
Chem. Phys. Lett., 115, 522 (1985).
16) Reciprocal Space Expansion in the Analysis of X-ray Scattering Intensities from Liquid CCl ４ .
K. Nishikawa and T. Iijima
Bull. Chem. Soc. Jpn., 59, 117 (1986).
17) Structure Model for Liquid Neopentane.
K. Nishikawa
Bull. Chem. Soc. Jpn., 59, 2920 (1986).
18) Determination of Energy Spectrum of the Primary Beam in Energy-Dispersive Diffractometry.
K. Nishikawa, K. Ishizawa, K. Kodera and T. Iijima
Jpn. J. Appl. Phys., 25, 1431(1986).
19) Simple Relationship between the Kirkwood-Buff Parameters and the Fluctuations of the Particle
Number and Concentration Obtained by Small-Angle X-ray Scattering.
K. Nishikawa
Chem. Phys. Lett., 132, 50 (1986).
20) Structure Study on Liquid 1,1,1-trichloroethane Using Energy-Dispersive Diffractometer.
(in Japanese)
K. Nishikawa, K. Nagano, T. Iijima
Journal of the Chemical Society of Japan, 1479 (1986).

21) Fluctuations in the Particle Number and Concetration and the Kirkwood-Buff Parameters oftert-Butyl Alcohol and Water Mixtures Studied by Small-Angle X-ray Scattering.
K. Nishikawa, Y. Kodera and T. Iijima
J. Phys. Chem., 91, 3694 (1987).
22) Binding and Correlation Effects in Nitrogen and Oxygen and the Correlation Effects in Neon,as Studied by Gas X-ray Diffraction.
K. Nishikawa and T. Iijima
J. Chem. Phys., 87, 3753 (1987).
23) Structural Study of Liquid 1,1,1-Trichloroethane by X-ray Diffraction.
K. Nishikawa and T. Iijima
Bull. Chem. Soc. Jpn., 61, 217 (1988).
24) X-ray Inelastic Scattering Intensity Measured by the Energy-Dispersive Diffractometry.
T. Iijima and K. Nishikawa
J. Appl. Cryst., 21, 943 (1988).
25) Temperature Dependence of the Concentration Fluctuation, the Kirkwood-Buff Parameters and theCorrelation Length of tert-Butyl Alcohol and Water Mixtures Studied by Small-Angle X-ray
Scattering.

K. Nishikawa, H. Hayashi and T. Iijima
J. Phys. Chem., 93, 6559 (1989).
26) Construction of a Small-Angle X-ray Scattering Diffractometer for Study of Fluctuations in
Solutions.
H. Hayashi, K. Nishikawa and T. Iijima
Jpn. J. Appl. Phys., 28, 1501 (1989).
27) The Micropore Swelling of Activated Carbon Fibers with Water Adsorption Studied by Use ofin situ Small-Angle X-ray Scattering.
K. Kaneko, Y. Fujiwara and K. Nishikawa
J. Colloid Interface Sci., 127, 298 (1989).
28) Easy Deduction of the Formula Relating the Fluctuations of a Binary System to the X-ray
Scattering Intensity Extrapolated to s = 0.
H. Hayashi, K. Nishikawa and T. Iijima
J. Appl. Cryst., 23, 134 (1990).
29) Structural Study of tert-Butyl Alcohol and Water Mixtures by X-ray Diffraction.
K. Nishikawa and T. Iijima
J. Phys. Chem., 94, 6227 (1990).
30) Small-Angle X-ray Scattering Study of Fluctuations in 1-Propanol-Water and 2-Propanol- Water
Systems.
H. Hayashi, K. Nishikawa and T. Iijima
J. Phys. Chem., 94, 8334 (1990).
31) Surface Fractal Dimension of Microporous Carbon Fibers by Nitrogen Adsorption.
K. Kaneko, M. Sato, T. Suzuiki, Y. Fujiwara K. Nishikawa and M. Jaroniec
J. Chem. Soc. Faraday Trans., 87, 179 (1991).
32) Accuracy of Intensity Measurement by Use of an Area Detector with a Photostimulable Phospher
Screen, as Confirmed by Measuring Scattering Intensity from a Liquid.
K. Nishikawa, Y. Sakamoto and T. Iijima
Jpn. J. Appl. Phys., 30, 1303 (1991).
33) A Simulation Study of Small-Angle X-ray Scattering Behavior of Activated Carbon Fibers
Adsorbing Water.
Y. Fujiwara, K. Nishikawa, T. Iijima and K. Kaneko
J. Chem. Soc. Faraday Trans., 87, 2763 (1991).
34) Small-Angle X-ray Scattering Study of Fluctuations in Ethanol and Water Mixtures.
K. Nishikawa and T. Iijima
J. Phys. Chem., 97, 10824 (1993).
35) Construction of Sample Holder for X-ray Diffraction Experiments on Supercritical Fluids.
K. Nishikawa and M. Takematsu
Jpn. J. Appl. Phys., 32, 5155-5158 (1993).
36) Structure Model of Liquid Water as Investigated by the Method of Reciprocal Space Expansion.
T. Iijima and K. Nishikawa
J. Chem. Phys., 101, 5017 (1994).
37) X-ray Scattering Study of Carbon Dioxide at Supercritical States.
K. Nishikawa and M. Takematsu
Chem. Phys. Lett., 226, 359-363 (1994).

38) Anomalous X-ray Scattering from Aqueous 2-Butoxyethanol at x BE =0.06 near Freezing.
Y. Koga, K. Nishikawa, K. Yoshino, I. Tanaka, Y. Yu and Y. Amemiya
Chem. Phys. Lett., 228, 53 (1994).
39) An X-ray Diffraction Study of the Structure and Molecular Motion in Liquid CS 2 .
T. Iijima and K. Nishikawa
J. Mol. Struct., 352/353, 213 (1995).
40) An Ordered Water Molecular Assembly Structure in a Slit-shaped Carbon Nanospace.
T. Iiyama, K. Nishikawa, T. Otowa and K. Kaneko
J. Phys. Chem., 99, 10075 (1995).
41) Correlation Lengths and Density Fluctuations in Supercritical State of Carbon Dioxide.
K. Nishikawa and I. Tanaka
Chem. Phys. Lett., 244, 149-152 (1995).
42) Small-angle X-ray Scattering Study of Supercritical Carbon Dioxide.
K. Nishikawa, I. Tanaka and Y. Amemiya,
J. Phys. Chem., 100, 418-421 (1996).
43) Small-angle X-ray Scattering Study of Supercritical CF 3 H.
K. Nishikawa and T. Morita,
J. Phys. Chem. B 101, 1413-1418 (1997).
44) Molecular Assembly Structure of CCl 4 in Graphitic Nanospaces.
T. Iiyama, K. Nishikawa, T. Suzuiki, T. Otowa, M. Hijiriyama, Y. Nojima and K. Kaneko
J. Phys. Chem. B 101, 3037 (1997).
45) Reply to Comment on the Correlation Lengths and Density Fluctuations in Supercritical State ofCarbon Dioxide.
K. Nishikawa,Chem. Phys. Lett., 271, 188 (1997).
46) Structure Study of Supercritical CO 2 near Higher-Order Phase Transition Line by X-ray
Diffraction.
T. Morita, K. Nishikawa, M. Takematsu, H. Iida and S. Furutaka
J. Phys. Chem. B 101, 7158-7162 (1997).
47) Study of the Structure of Water Molecular Assembly in a Hydrophobic Nanospace at Low
Temperature with in situ X-ray Diffraction.
T. Iiyama, K. Nishikawa, T. Suzuki and K. Kaneko
Chem. Phys. Lett., 274, 152-158 (1997).
48) Fluid Behavior at Supercritical States Studied by Small-Angle X-Ray Scattering.
K. Nishikawa and T. Morita
J. Supercritical Fluids 13, 143-148 (1998).
49) Influence of Fine Particles on Carbon Deposition in the Coke Oven Chamber.
T. Nakagawa, T. Suzuki, A. Furusawa, Y. Maeno, I. Komaki and K. Nishikawa
Fuel 77,1141-1146 (1998).
50) Study on Graphitization of Glassy Carbon Using Small-Angle X-Ray Diffractometry. (in Japanese)
K. Fukuyama, T. Nishizawa, K. Nishikawa
Carbon No. 182, 85-90 (1998).
51) Construction of the Sample Holder and Small-Angle X-ray scattering Measurement forSupercritical Water.
T. Morita, H. Miyagi, Y Shimokawa, H. Matsuo and K. Nishikawa
Jpn. J. Appl. Phys. 37, L768-770 (1998).
52) Structure Change of Glass-like Carbon with Heat Treatment, Studied by Small-Angle X-ray
Scattering: I Glass-like Carbon Prepared from Phenolic Resin
K. Nishikawa, K. Fukuyama and T. Nishizawa
Jpn. J. Appl. Phys. 37, 6486-6491 (1998).
53) Development of Thermal Conductivity Measurement for Fluids which is Convenient andEffective for Samples near the Critical Point.
Zai-hau Chen, K. Tozaki and K. Nishikawa
Jpn. J. Appl. Phy. 38, L91-94 (1999).
54) Change of Surface Fractal Dimension for Witbank Coal with Heat Treatment Studied by Small
Angle X-ray Scattering.
T. Nakagawa, K. Nishikawa and I. Komaki
Carbon 37, 520-522 (1999).
55) Pore-Width-Dependent Ordering of C 2 H 5 OH Molecules Contained in Graphitic Slit Nanopores.
T. Ohkubo, T. Iiyama, K. Nishikawa, T. Suzuiki and K. Kaneko
J. Phys. Chem. B 103, 1859 - 1863 (1999).
56) Evaluation and Countermeasures of Convective Heat Transfer on Thermal Conductivity
Measurement Using the Peltier Effect and Application to Supercritical CO 2 .
Z. Chen, K. Tozaki and K. Nishikawa
Jpn. J. Appl. Phys. 38, 6840 - 6845 (1999).
57) Fractal Structural Change of Witbank Coal with Heat Treatment Studied by Small Angle X-ray
Scattering.
T. Nakagawa, I. Komaki, M. Sakawa and K. Nishikawa
Fuel 79, 1341-1346 (2000).
58) Construction of Small-angle X-ray Scattering Diffractometer by Use of Asymmetric-Cut
Monochromator.
Y. Kasahara and K. Nishikawa
Jpn. J. Appl. Phys. 39, Part 1, 343-344 (2000).
59) Inhomogeneity of Molecular Distribution in Supercritical Fluids.
K. Nishikawa and T. Morita
Chem. Phys. Lett. 316, 238-242 (2000).
60) Study of Inhomogeneity of Supercritical Water by Small-angle X-ray Scattering.
T. Morita, K. Kusano, H. Ochiai, K. Saitow and K. Nishikawa
J. Chem. Phys. 112, 4203-4211 (2000).
61) Raman Spectral Changes of Neat CO 2 across the Ridge of Density Fluctuation in Supercritical
Region.
H. Nakayama, K. Saitow, M. Sakashita, K. Ishii and K. Nishikawa
Chem. Phys. Lett. 320, 323-327 (2000).
62) A Thermodynamic Study of Aqueous Acetonitrile: Excess Chemical Potentials, Partial Molar
Enthalpies, Entropies and Volumes, and Fluctuations.
P. V. Nikolova, S. J. B. Duff, P. Westh, C. A. Haynes, Y. Kasahara, K. Nishikawa and Y. Koga
Can. J. Chem., 78, 1553-1560 (2000).

63) Supercritical-Fluid Cell with Device of Variable Optical Path Length Giving Fringe-Free
Terahertz Spectra.
K. Saitow, K. Nishikawa, H. Ohtake, N. Sarukura, H. Miyagi, Y. Shimokawa, H. Matsuo andK. Tominaga
Rev. Sci. Instrm., 71, 4061-4064 (2000).
64) Small-angel X-ray Scattering Study on Pore Structure of Carbon Fiber Prepared from Polymer
Blend of Phenolic Resin and Polystyrene.
K. Fukuyama, Y. Kasahara, N. Kasahara, A. Oya and K. Nishikawa
Carbon 39, 287-290 (2001).
65) Effect of Hot Isostatic Pressing on Nanopore in Glass-like Carbon Prepared from Phenol
Formaldehyde Resin.
K. Fukuyama, T. Nishizawa and K. Nishikawa
Carbon 39, 1863-1867 (2001).
66) Investigation of Pore Structure in Glass-like Carbon Prepared from Furan Resin.
K. Fukuyama, T. Nishizawa and K. Nishikawa
Carbon 39, 2017-2021 (2001).
67) Construction of a Sample Cell of Poisonous Organic Solvents in Supercritical State for SmallAngle X-ray Scattering Measurements.
A. Ayusawa, K. Kusano, T. Morita, H. Miyagi, Y. Shimokawa, H. Matsuo and K. Nishikawa
Jpn. J. Appl. Phys. 40, 4260-61 (2001).
68) Terahertz Absorption Spectra of Supercritical CHF 3 to Investigate Local Structure throughRotational and Hindered Rotational Motions.
K. Saitow, H. Ohtake, N. Sarukura and K. Nishikawa
Chem. Phys. Lett. 341, 86-92 (2001).
69) Titanium Sample Holder for Small-Angle X-ray Scattering Measurements of Supercritical Aqueous
Solutions.
T. Morita, K. Kusano, K. Nishikawa, H. Miyagi, Y. Shimokawa and H. Matsuo
Rev. Sci. Instrm. 72, 3013-3018 (2001).
70) Mixing Schemes of Aqueous Dimethyl Sulfoxide: A Support by X-ray Diffraction Data.
Y. Koga, Y. Kasahara, K. Yoshino and K. Nishikawa
J. Sol. Chem. 30, 885-893 (2001).
71) Inhomogeneity of Mixing in Acetonitrile Aqueous Solution Studied by Small-Angle X-ray Scattering.
K. Nishikawa , Y. Kasahara and T. Ichioka
J. Phys. Chem. B 106, 693-700 (2002)
72) Correlation Time of Density Fluctuation for Supercritical Ethylene Studied by Dynamic Light
Scattering.
K. Saitow, H. Ochiai, T. Kato and K. Nishikawa
J. Chem. Phys. 116, 4985-4992 (2002).
73) Density-Fluctuation-Induced Swelling of Polymer Thin Films in Carbon Dioxide.
T. Koga, Y-S. Seo, Y. Zhang, K. Shin, K. Kusano, K. Nishikawa, M. H. Rafailovich,J. C. Sokolov, B. Chu. D. Peiffer, and S. K. Satija
Phys. Rev. Lett. 89, 125506-1 – 125506-4 (2002).
74) Development of an Apparatus for High-Resolution Measurement of Permittivity for Fluids near the
Critical Point and Detection of the Critical Anomaly on Supercritical Ethylene.

K. Tozaki, J. Kudo, Z. Chen and K. Nishikawa
Jpn J. Appl. Phys. 41, 6455−6460 (2002).
75) Pore Structure in Carbon Fibers Prepared from Polymer Blend.
K. Fukuyama, T. Hoshino, K. Nishikawa and A. Oya
Mol. Crys. Liq. Cryst., 388, 471-475 (2002).
76) Static Inhomogeneity of Supercritical Ethylene Studied by Small-Angle X-ray Scattering.
K. Nishikawa, H. Ochiai, K. Saitow and T. Morita
Chem. Phys. 286, 421-430 (2003).
77) Density Fluctuation of a van der Waals Fluid at Supercritical State.
K. Nishikawa, K. Kusano, A. A. Arai and T. Morita
J. Chem. Phys. 118, 1341-1346 (2003).
78) Local Density Enhancement in neat Superrcritical Fluid due to Attractive Intermolecular Interactions.
K. Saitow, K. Otake, H. Nakayama, K. Ishii and K. Nishikawa
Chem. Phys. Lett. 368, 209-214 (2003).
79) Chemical Potential and Concentration Fluctuation in Some Aqueous Alkane-mono-ols at 25 ℃.
J. Hu, C. A. Haynes, A. H. Y. Wu, C. M. W. Chang, M. G. M. Chen, E. G. M. Yee, T. Ichioka,
K. Nishikawa and Y. Koga
Can. J. Chem. 81, 141-149 (2003).
80) Excess Partial Molar Entropy of Alkane-mono-ols in Aqueous Solutions at 25 ℃.
Y. Koga, P. Westh and K. Nishikawa
Can. J. Chem. 81, 150-155 (2003)
81) Investigation of Structural Fluctuation of Supercritical Benzene by Small-angle X-ray Scattering.
A. A. Arai, T. Morita and K. Nishikawa
J. Chem. Phys. 119, 1502-1509 (2003)
82) X-ray Absorption Fine Structure Study on Residue Bromine in Carbons with Different Graphitization
Degree.
H. Yoshikawa, K. Fukuyama, Y. Nakahara, T. Konishi, N. Ichikuni, Y. Yoshikawa, N. Akuzawa,Y. Takahashi and K. Nishikawa
Carbon 41, 2931-2938 (2003).
83) Dynamics of Density Fluctuation of Supercritical Fluid Mapped on Phase Diagram.
K. Saitow, D. Kajiya and K. Nishikawa
J. Am. Chem. Soc., 126, 422-423 (2004).
84) The Effects of Na 2 SO 4 and NaClO 4 on the Molecular Organization of H 2 O.
Y. Koga, P. Westh and K. Nishikawa
J. Phys. Chem. A 108, 1635-1637 (2004).
85) “Icebergs” or No “Icebergs” in Aqueous Alcohols? Composition-dependent Mixing Schemes.
Y. Koga, K. Nishikawa and P. Westh
J. Phys. Chem. A 108, 3873-3877 (2004).
86) Density Fluctuation of Supercritical Fluids Obtained from Small-angle X-ray Scattering Experimentand Thermodynamic Calculation.
K. Nishikawa, A. A. Arai and T. Morita
J. Supercritical Fluids 30, 249-257 (2004).
87) How are Hydrogen Bonds Perturbed in Aqueous NaClO 4 Solution Depending on the Concentration?

A Near Infrared Study of Water.
K. Saitow, K. Kobayashi and K. Nishikawa
J. Sol. Chem. 33, 685-694 (2004).
88) Fluctuations in Density and Concentration of Methanol-Water Mixtures at 7 MPa and 373, 423 K
Studied by Small-Angle X-ray Scattering.
T. Morita and K. Nishikawa
Chem. Phys. Lett. 389, 29-33 (2004)89) The Structure Study of Room-Temperature Ionic Liquid 1-n-butyl-3-methylimidazolium Iodide
Utilizing Wide-Angle X-ray Scattering and Raman Spectroscopy.
H. Katayanagi, S. Hayashi, H. Hamaguchi and K. Nishikawa
Chem. Phys. Lett. 392,460-464 (2004).
90) Attractive and Repulsive Intermolecular Interactions of a Polar Molecule: Short-range Structure of
Neat Supercritical CHF 3 Investigated by Raman Spectroscopy.
K. Saitow, H. Nakayama, K. Ishii and K. Nishikawa
J. Phys. Chem. A 108, 5770-5784 (2004).
91) Towards Understanding the Hofmeister Series (1): The Effect of Sodium Salts of Some Anions on the
Molecular Organization of H 2 O.
Y. Koga, P. Westh, J. V. Davies, K. Miki, K. Nishikawa H. Katayanagi
J. Phys. Chem. A 108 8533-8541 (2004).
92) Mixing Schemes in Ionic Liquid– H 2 O Systems: A thermodynamic study.
H. Katayanagi, K. Nishikawa, H. Shimozaki, K. Miki, P. Westh and Y. Koga
J. Phys. Chem. B 108,19451-19457 (2004).
93) Mesocellular Foam Carbons: Aggregates of Hollow Carbon Spheres with Open and Closed Wall
Structures.
Y. Oda, K. Fukuyama, K. Nishikawa, S. Namba, H. Y. and T. Tatsumi
Chem. Mater. 16, 3860-3866 (2004).
94) Novel detection method of Liquid-Liquid phase separation
H. Kato, H. Katayanagi, Y. Koga and K. Nishikawa
Jpn. J. Appl. Phys. 43, 8217-8218 (2004).
95) Analysis to obtain precise density fluctuation of supercritical fluids by small-angle X-ray scattering
A. A. Arai, T, Morita and K. Nishikawa
Chem. Phys. 310, 123-128 (2005).
96) Time Evolution of Density Fluctuation in Supercritical Region: Part I. Nonhydrogen Bonded Fluids
Studied by Dynamic Light Scattering.
K. Saitow, D. Kajiya and K. Nishikawa
J. Phys. Chem. A 109, 83-91 (2005)97) Volume-variable sample holder for small-angle X-ray scattering measurements of supercriticalsolutions and application to a CHF 3 -CO 2 mixture
T. Morita, T. Masakawa, A. A. Arai, M. Nakagawa and K. Nishikawa
Rev. Sci. Instrm. 76, 033902/1-033902/4 (2005).
98) Br K-edge XANES Analyses of Bromine Residue Carbon Compounds by Full Multiple Scattering
Theory.
K. Uno, Y. Notoya, T. Fujikawa, H. Yoshikawa and K. Nishikawa.
Jpn. J. Appl. Phys. 44, 4073-4079 (2005).

99) Effect of an “ionic liquid” cation, 1-butyl-3-methylimidazolium, on the Molecular Organizationof H 2 O.
K. Miki, P. Westh, K. Nishikawa, and Y. Koga
J. Phys. Chem. B 109, 9014-9019 (2005).
100) Time Evolution of Density Fluctuation in Supercritical Region: Part 2. Comparison of
Hydrogen- and Non-hydrogen- Bonded Fluids
D. Kajiya K. Nishikawa and K. Saitow
J. Phys. Chem. A 109, 7365-7370 (2005)
101) Novel method to measure heat capacity of supercritical fluids by using the Peltier elements.
K. Tozaki, Y. Kido, Y. Koga and K. Nishikawa
Jpn J. Appl. Phys. 45, 269-273 (2006).
102) Density Dependences of Long-range Fluctuations and Short-range Correlation Lengths of CHF 3 andCH 2 F 2 in Supercritical State.
T. Morita, Y. Takahashi, Y. Tanaka, A. A. Arai and K. Nishikawa
J. Chem. Phys. 124, 124549/1-6 (2006).
103) Air oxidation of Carbon Spheres II Micropore Development
M. Inagaki, T. Nishikawa, K. Oshida, K. Fukuyama, Y. Hatakeyama, and K. Nishikawa
Adsorption Science and Technology 24, 55-64 (2006).
104) The effects of chloride salts of some cations on the molecular organization of H 2 O：Towards
understanding the Hofmeister series (II).
Yoshikata Koga, Hideki Katayanagi, James V. Davies, Hitoshi Kato, Keiko Nishikawa, andPeter Westh
Bull. Chem. Soc. Jpn. 79, 1347-1354 (2006).
105) Towards understanding the Hofmeister series (III): Effects of sodium halides on the molecularorganization of H 2 O as probed by 1-propanolPeter Westh, Hitoshi Kato, Keiko Nishikawa, Yoshikata Koga.
J. Phys. Chem. A 110, 2072-2078 (2006)106) Development of polarized Raman spectrometer for supercritical fluids having high critical points.
K. Otake, M. Abe, K. Nishikawa and K. Saitow
Jpn. J. Appl. Phys. 45 A 2801-2806 (2006).
107) Br K-edge XAFS Analyses of IBr Residue Carbon Compounds.
H. Yoshikawa, K. Uno, N. Akuzawa, T. Konishi, T. Fujjikawa and K. Nishikawa
Carbon (submitted)108) Anomalous dynamic behavior of ions and water molecules in dilute aqueous solution of
1-butyl-3-methylimidazolium bromide studied by NMR.
M. Nakakoshi, S. Ishihara, H. Utsumi, H. Seki, Y. Koga, and K. Nishikawa
Chem. Phys. Lett. 427, 87-90 (2006).
109) Crystal Structure of 1-Butyl-3-methylimidazolium Iodide.
M. Nakakoshi, M. Shiro, T. Fujimoto, T. Machinami, H. Seki, M. Tashiro and K. Nishikawa
Chem. Lett. 35, 1400 -1401(2006).
110) Investigation on structural fluctuation of supercritical cyclohexane by small-angle X-ray scattering
A. A. Arai, T. Morita and K. Nishikawa
Fluid Phase Equilibria 252, 114-118 (2007).
111) Apparatus for simultaneous measurement of X-ray absorption factor developed for small-angle

X-ray scattering beam line.
T. Morita, Y. Tanaka, K. Ito, Y. Takahashi and K. Nishikawa
J. Appl. Cryst 40, 791-795 (2007).
112）Crystal Structure of 2,3-Dimethyl-1-propylimidazolium Bromide.
T. Fujumoto, M. Nakakoshi, T. Machinami, H. Seki, K. Nishikawa and M. Tashiro
Anal. Sci. 23, X9-X10 (2007).

113) Melting and freezing behaviors of prototype ionic liquids, 1-butyl-3-methylimidazolium bromide
and its chloride, studied by using a nano-Watt differential scanning calorimeter.
K Nishikawa, S. Wang, H. Katayanagi, S. Hayashi, H. Hamaguchi, Y. Koga, and K Tozaki
J. Phys. Chem. B 111, 4894-4900 (2007).
114) Crystal Structure of 2,3-Dimethyl-1-isopropylimidazolium Bromide
T. Fujumoto, M. Kawahata, M. Nakakoshi, K. Yamaguchi, T. Machinami, H. Seki, K. Nishikawa
and M. Tashiro
Anal. Sci. 23, X107-X108 (2007).
115) Relative Hydrophobicity/Hydrophilicity of Fructose, Glucose, Sucrose and Trehalose as probed by
1-Propanol: A Differential Approach in Solution Thermodynamics
Yoshikata Koga*, Keiko Nishikawa, Peter Westh
J. Phys. Chem. B 111, No. 50 13943-13948 (2007).
116) Sample Holder for Small-Angle X-ray Scattering Measurements and Density Fluctuation ofSupercritical Xenon.
Yoshitada Tanaka, Yoshihiro Takahashi, Takeshi Morita and Keiko Nishikawa
Jpn. J. Appl. Phys. 47 (1), 334-336 (2008).
117）Development of an Apparatus for Simultaneous Measurements of Raman spectroscopy andHigh-Sensitive Calorimetry.
Takatsugu Endo, Ken-ichi Tozaki, Takashi Masaki and Keiko Nishikawa
Jpn. J. Appl. Phys. 47 (3), 1775-1779 (2008).
118) Relative hydrophobicity and hydrophilicity of some “ionic liquid” anions determined by the
1-propanol probing methodology: A differential thermodynamic approach.
Hitoshi Kato, Keiko Nishikawa and Yoshikata Koga
J. Phys. Chem. B 112, No. 9 2655-2660 (2008).
119) Rhythmic Melting and Crystallizing of Ionic Liquid 1-Butyl-3-methylimidazolium Bromide
Keiko Nishikawa, Shaolan Wang, and Ken-ichi Tozaki
Chem. Phys. Lett., 458, 88-91 (2008).
120) Conformational Analysis of 1-Butyl-3-methylimidazolium by CCSD(T) level Ab Initio Calculations:
Effects of Neighboring Anions
Seiji Tsuzuki, Asako Ayusawa Arai and Keiko Nishikawa
J. Phys. Chem. B, 112, 7739-7747 (2008).
121) Self aggregation of 1-butyl-3-methylimidazolium bromide in aqueous solution.
H. Tsuchiya, M. Imanari, S. Ishihara, M. Nakakoshi, K. Nishikawa, H. Seki and M. Tashiro
Anal. Sci., 24, 1369-1371(2008).
122) 1H NMR Study on reorientational dynamics of an ionic liquid, 1-butyl-3-methylimidazolium
bromide, accompanied with phase transitions.
M. Imanari, M. Nakakoshi, H. Seki and K. Nishikawa

Chem. Phys. Lett., 459, 89-93 (2008).
123) Isomer Populations in Liquids for 1-Isopropyl-3-methylimidazolium Bromide and Its Iodide, andTheir Conformational Changes Accompanying the Crystallizing and Melting Processes.
Takatsugu Endo and Keiko Nishikawa
J. Phys. Chem. A, 112, 7543-7550 (2008).
124) Intermittent crystallization of an ionic liquid: 1-Isopropyl-3-methylimidazolium Bromide.
Keiko Nishikawa and Ken-ichi Tozaki
Chem. Phys. Lett., 463, 369-372 (2008).
125) Chemical Potentials in Aqueous Solutions of Some Ionic Liquids with 1-Ethyl-3-methylimidazolium
Cation.
Hitoshi Kato, Keiko Nishikawa, Hiromi Murai, Takeshi Morita, and Yoshikata Koga
J. Phys. Chem. B 112, 13344-13348 (2008).
126) Characterization of the molecular reorientational dynamics of the neat ionic liquid 1-butyl3-methylimidazolium bromide in the super cooled state using 1H and 13C NMR spectroscopy.
Mamoru Imanari, Hiroyuki Tsuchiya, Hiroko Seki, Keiko Nishikawa and Mitsuru Tashiro
Mag. Res. Chem. 47, 67-70 (2009).
127) Small-Angle X-ray Scattering Study on Au Nanoparticles Dispersed in Ionic Liquids of
1-Alkyl-3-Methylimidazolium Tetrafluoroborate
Yoshikiyo Hatakeyama, Maimi Okamoto, Tsukasa Torimoto, Susumu Kuwabata, Keiko Nishikawa
J. Phys. Chem. C 113 (10), 3917-3922 (2009).
128) Interpretation of Correlation Length in Small-angle X-ray Scattering Experiments on fluids near
critical point.
Hisashi Hayashi, Takeshi Morita, and Keiko Nishikawa
Chem. Phys. Lett. 471, 249-252 (2009).
129) Halogen-bonded and hydrogen-bonded network structures in crystals of 1-propyl- and 1-butyl-4,5dibromo-3-methylimidazloium bromides.
Tomohiro Mukai and Keiko Nishikawa
Chem. Lett. 38, No. 5, 402-403 (2009).
130) Atomic Mass Effects of [XF 6 ]- ionic Liquids. I. Experimental Study.
Hideki Shirota, Keiko Nishikawa and Tateki Ishida
J. Phys. Chem. B 113, 9831-9839 (2009).
131) Atomic Mass Effects of [XF 6 ]- ionic Liquids. II. Theoretical Study.
Tateki Ishida, Keiko Nishikawa and Hideki Shirota
J. Phys. Chem. B 113, 9840-9851 (2009).
132) Melting and Crystallization Behaviors of an Ionic Liquid, 1-Isopropyl-3-methylimidazolium
Bromide, Studied by Using Nanowatt-Stabilized Differential Scanning Calorimetry.
Keiko Nishikawa, Shaolan Wang, Takatsugu Endo, and Ken-ichi Tozaki
Bull. Chem. Soc. Jpn. 82 (7), 806-812 (2009).
133) Spectrum of Excess Partial Molar Absorptivity. I : Near Infrared Depectroscopic Study of Aqueous
Acetonitrile and Acetone."
Yoshikata Koga, Fumie Sebe, Takamasa, Mimami, Keiko Otake, Ken-Ichi Saitow, Keiko Nishikawa
J. Phys. Chem. B 113 11928-11935 (2009).
134) Multiple Small-angle X-ray Scattering Analyses of the Structure of Gold Nanorod with Unique
End Caps.

Takeshi Morita, Yoshikiyo Hatakeyama, Keiko Nishikawa, Eiichi Tanaka, Rie Shingai, Hiromi
Murai, Hirofumi Nakano, and Kazuyuki Hino
Chem. Phys. 364 14-18 (2009).
135) Thermodynamic Study on Phase Transitions of Poly(benzyl methacrylate) in Ionic Liquids Solvent
Takeshi Ueki, Asako Ayusawa Arai, Koichi Kodama, Sayaka Kaino, Noriko Takada, Takeshi
Morita, Keiko Nishikawa, and Masayoshi Watanabe
Pure & Applied Chemistry 81, 1829-1841 (2009).
136) Hydrophobicity/Hydrophilicity of 1-Butyl-2,3-dimethyl and 1-Ethyl-3-methylimodazolium Ions:
Towards Characterization of Room Temperature Ionic Liquids
Hitoshi Kato, Kumiko Miki, Tomohiro Mukai and Keiko Nishikawa
J. Phys. Chem., 113, 14754-14760 (2009).
137) Ultrafast Dynamics in Aprotic Molecular Liquids: A Femtosecond Raman-Induced Kerr Effect
Spectroscopic Study.
Hideki Shirota, Tomotsumi Fijisawa, Hiroki Fukazawa and Keiko Nishikawa
Bull. Chem. Soc. Jpn. 82 (11), 1347-1366 (2009).
138) Polymorphic Properties of Ionic Liquid of 1-Isopropyl-3-methylimidazolium Bromide
Masatoshi Kawahata, Takatsugu Endo, Hiroko Seki, Keiko Nishikawa, and Kentaro Yamaguchi
Chem. Lett. 38(12) 1136-1137(2009).
139) Comparison of Interionic/Intermolecular Vibrational Dynamics between Ionic Liquids andConcentrated Electrolyte Solutions.
Tomotsumi Fujisawa, Keiko Nishikawa, and Hideaki Shirota
J. Chem. Phys. 131, 244519_1-14(2009).
140) Phase Behaviors of Room Temperature Ionic Liquid Linked with Cation Conformational Changes:
1-Butyl-3-methylimidazolium Hexafluorophosphate
Takatsugu Endo, Tatsuya Kato, Ken-ichi Tozaki, Keiko Nishikawa
J. Phys. Chem. B 114, 407-411 (2010).
141) Aspect-Ratio Dependence on Formation Process of Gold Nanorods Studied by Time-Resolved
Distance Distribution Functions.
Takeshi Morita, Eiichi Tanaka, Yukihiro Inagaki, Hiroyasu Hotta, Rie Shingai, Yoshikiyo
Hatakeyama, Keiko Nishikawa, Hiromi Murai, Hirofumi Nakano, and Kazuyuki Hino
J. Phys. Chem. C 114, 3804-3810 (2010).
142) NMR study on relationships between reorientational dynamics and phase behaviour ofroom-temperature ionic liquids: 1-alkyl-3-methylimidazolium cations
Mamoru Imanari, Kei-ichi Uchida, Kozue Miyano, Hiroko Seki and Keiko Nishikawa
Phys. Chem. Chem. Phys. 12, 2959-2967 (2010). (Cover Article of No.12 Vol. 12)143) Zigzag Sheet structure in halogen-bonding imidazolium salt:
1-butyl-4,5-dibromo-3-methylimidazolium iodide
Tomohiro Mukai and Keiko Nishikawa
X-ray Structure Analysis online 26, 31-32 (2010).
144) Syntheses and crystal structures of two ionic liquids having halogen-bonding groups:
4,5-Dibromo- and 4,5-diiodo-1-butyl- -3-methylimidazolium trifluoromethanesulfonates
Tomohiro Mukai and Keiko Nishikawa
Solid State Science 12, 783-788 (2010).
145) Microscopic Study of Ionic Liquid-H 2 O Systems: Alkyl-Group Dependence of 1-Alkyl-3-

Methylimidazolium Cation.
T. Masaki, K. Nishikawa, H. Shirota
J. Phys. Chem. B 114, 6323–6331 (2010).
146) Can Temperature Control the Size of Au Nanoparticles Prepared in Ionic Liquids by Sputter
Deposition Technique?
Yoshikiyo Hatakeyama, Satoshi Takahashi, Keiko Nishikawa
J. Phys. Chem. C 114,11098–11102 (2010).
147) Halogen bonding and hydrogen bonding in 4,5-diiodo-3-methyl-1-propylimidazolium
hexafluorophosphate
Tomohiro Mukai and Keiko Nishikawa
X-ray Structure Analysis online 26, 39-40 (2010).
148) Effects of Methylation at the 2 Position of the Cation Ring on Phase Behaviors and Conformational
Structures of Imidazolium-Based Ionic Liquids
Takatsugu Endo, Tatsuya Kato, and Keiko Nishikawa
J. Phys. Chem. B 114, 9201–9208 (2010).
149) Synthesis of Gold Nanoparticles in Liquid Polyethylene Glycol by Sputter Deposition andTemperature Effects on their Size and Shape.
Yoshikiyo Hatakeyama, Takeshi Morita, Satoshi Takahashi, Kei Onishi, and Keiko Nishikawa
J. Phys. Chem. C 115, 3279–3285(2011).
150) Is a Methyl Group always Hydrophobic? : Hydrophilicity of Trimethylamine-N-oxide, Tetramethyl
Urea and Tetramethylammonium Ion
Yoshikata Koga, Peter Westh, Keiko Nishikawa, and S. SubramanianJ. Phys. Chem. B 115, 2995-3002 (2011).
151) Effects of Methylation at Position 2 of Cation Ring on Rotational Dynamics of Imidazolium-based
Ionic Liquids Investigated by NMR Spectroscopy: [C 4 mim]Br vs [C 4 C 1 mim]Br
Takatsugu Endo, Mamoru Imanari, Hiroko Seki, and Keiko Nishikawa
J. Phys. Chem. A 115, 2999-3005 (2011).
152) High-Resolution Calorimetry on Thermal behavior of Glycerol (1): Glass transition, crystallizationand Melting, and Discovery of a Solid-Solid transition.
Kalyan Sou, Keiko Nishikawa, Yoshikata Koga and Ken-ichi Tozaki
Chem. Phys. Lett., 506, 217-220 (2011).
153) Correlation between Hydrocarbon Flexibility and Physicochemical Properties for
Cyclohexyl-imidazolium Based Ionic Liquids Studied by 1H and 13C NMR
Toshihiko Mandai, Mamoru Imanari, and Keiko Nishikawa
Chem. Phys. Lett., 507, 100-104 (2011).
154) Crystal polymorphism of a room-temperature ionic liquid, 1,3-dimethylimidazolium
hexafluorophosphate: Calorimetric and structural studies of two crystal phases having melting pointsof ~50K difference.
Takatsuge Endo, Takeshi Morita, and Keiko Nishikawa
Chem. Phys. Lett., 517, 162-165 (2011).
155) Effects of Sputtering Conditions on Formation of Gold Nanoparticles in Sputter Deposition
Technique.
Yoshikiyo Hatakeyama, Kei Onishi and Keiko Nishikawa
RSC (Royal Society of Chemistry) Advances, 1, 1815-1821 (2011).

156) Cation and Anion Dynamics in Supercooled and Glass States of the Ionic Liquid
1-Butyl-3-methylimidazolium Hexafluorophosphate: Results from 13C, 31P, and 19F NMR
spectroscopy.
Takatsugu Endo, Scarlett Widgeon, Ping Yu, Sabyasachi Sen and Keiko Nishikawa
Phys. Rev. B 85, 054307-1~ -9 (2012).
157) Comparison between Cycloalkyl- and n-Alkyl-Substituted Imidazolium-Based Ionic Liquids inPhysicochemical Properties, Reorientational Dynamics.
Toshihiko Mandai, Hyuma Masu, Mamoru Imanari, and Keiko Nishikawa
J. Phys. Chem. B, 116, 2059-2064 (2012).
158) Effects of Cyclic-Hydrocarbon Substituents and Linker Length on Physicochemical Properties andReorientational Dynamics of Imidazolium-Based Ionic Liquids.
Toshihiko Mandai, Akiko Matsumura, Mamoru Imanari, and Keiko Nishikawa
J. Phys. Chem. B, 116, 2090-2095 (2012).
159) Spectrum of Excess Partial Molar Absorptivity. II: An NIR Study of Aqueous Na-Halides.
Fumie Sebe, Keiko Nishikawa, and Yoshikata Koga
Phys. Chem. Chem. Phys., 14, 4433-4439 (2012).
160) NMR Study of Cation Dynamics in Three Crystalline States of 1-Butyl-3-Methylimidazolium
Hexafluorophosphate Exhibiting Crystal Polymorphism
Takatsugu Endo, Hiroki Murata, Mamoru Imanari, Noriko Mizushima, Hiroko Seki,
Keiko Nishikawa
J. Phys. Chem. B 116, 3780-3788 (2012).
161) Ultraslow Dynamics at Crystallization of a Room-Temperature Ionic Liquid,
1-Butyl-3-methylimidazolium Bromide.
Mamoru Imanari, Kozo Fujii, Takatsugu Endo, Hiroko Seki, Ken-ichi Tozaki, Keiko Nishikawa
J. Phys. Chem. B 116, 3991-3997 (2012).
162) Dynamical scaling analysis using the Lillie Number for vitrification of deeply supercooled glycerol
Kalyan Sou, Keiko Nishikawa, Yoshikata Koga, Ken-ichi Tozaki
J. Non-Crystalline Solids, 358, 1313-1318 (2012).
163) Linker-Length Dependence of Crystal Structures and Thermal Properties of Bis-imidazolium Salts.
Toshihiko Mandai, Hyuma Masu, Hiroko Seki, and Keiko Nishikawa
Bull. Chem. Soc. Jpn., 85, 599–605 (2012).
164) Effects of ethanol and dimethylsufoxide on the molecular organization of H 2 O as probed by
1-propanol.
Takeshi Morita, Peter Westh, Keiko Nishikawa, Yoshikata Koga
J. Phys. Chem. B 116, 7328–7333 (2012).
165) Small-angle X-ray Scattering Measurements of Ionic Liquids pressurized with Carbon Dioxide
Using High–Pressure Titanium Sample Holder:
1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) Amide Mixtures up to 22 MPa
Takeshi Morita, Masayoshi Ushio, Kaori Kanoh, Eiichi Tanaka and Keiko Nishikawa
Jpn. J. Appl. Phys., 51, 076703-1~6 (2012).
166) Small-angle X-ray scattering study on the fluctuations of supercritical aqueous solution of n-pentane
along the critical isotherm of waterTakeshi Morita*, Hiromi Murai, Syunsuke Kase, Keiko Nishikawa
Chem. Phys. Lett., 543, 68–71 (2012).

167) Linker-length dependence of the reorientational dynamics and viscosity of bis(imidazolium)-basedionic liquids incorporating bis(trifluoromethanesulfonyl)amide anions
Toshihiko Mandai, Mamoru Imanari, Keiko Nishikawa
Chem. Phys. Lett., 543, 72–75 (2012).
168) Transglycosylated rutin induced non-surface active nanostructure for absorption enhancement of
flurbiprofen.
Y. Tozuka, K. Higashi, T. Morita, K. Nishikawa, H. Uchiyama, J. Zhang, K. Moribe, H. Takeuchi
and K. Yamamoto
European Journal of Pharmaceutics and Biopharmaceutics 82, 120-126 (2012).
169) Optical and radiographical characterization of silica aerogel for Cherenkov radiator”
M. Tabata, I. Adachi, Y. Hatakeyama, H. Kawai, T. Morita and K. Nishikawa
IEEE Transactions Nuclear Science 59, 2506-2511 (2012).
170) X-ray radiographic technique for measuring density uniformity of silica aerogel”
M. Tabata, Y. Hatakeyama, I. Adachi, T. Morita and K. Nishikawa
Nuclear Inst. and Methods in Physics Research A 697 52-58 (2013).
171) A comparative study of the rotational dynamics of PF 6 − anions in the crystals and liquid states of
1-butyl-3-methylimidazolium hexafluorophosphate : Results from 31P NMR spectroscopy
Takatsugu Endo, Hiroki Murata, Mamoru Imanari, Noriko Mizhisima, Hiroko Seki,
Sabyasachi Sen, and Keiko Nishikawa
J. Phys. Chem. B 117, 326–332 (2013).
172) Effects of Tetramethyl- and Tetraethyl-Ammonium Chloride on H 2 O: Calorimetric and Near Infrared
Spectroscopic Study.
Yoshikata Koga, Fumie Sebe, and Keiko Nishikawa
J. Phys. Chem. B 117, 877–883 (2013).
173) Crystal Structure of 1-Methy-2,4,5-Triiodolimidazole: Formation of Triangle-Shaped Trimmer
through Halogen Bonding.
Tomohiro Mukai and Keiko Nishikawa
X-ray Structure Analysis online 29, 13-14 (2013).
174) Fusion Growth of Gold Nanoparticles Induced by the Conformational Change of a
Thermoresponsive Polymer Studied by Distance Distribution Functions
Takeshi Morita, Kenta Kurihara, Osamu Yoshida, Hiroshi Imamura, Yoshikiyo Hatakeyama,
Keiko Nishikawa and Nobuo Uehara
J. Phys. Chem. C 117 (26), 13602–13608 (2013).
175) Thermal phase behavior of 1-butyl-3-methylimidazolium hexafluorophosphate: Simultaneous
measurements of the melting of two polymorphic crystals by Raman spectroscopy and calorimetry.
Takatsugu Endo and Keiko Nishikawa
Chem. Phys. Lett., 584, 79-82 (2013)176) Visible photoluminescence of gold nanoparticles prepared by sputter deposition technique in aroom-temperature ionic liquid
Toshifumi Iimori, Yoshikiyo Hatakeyama, Keiko Nishikawa, Masako Kato, Nobuhiro Ohta
Chem. Phys. Lett., 586, 79-82 (2013).
177) Modulation of the intermolecular interaction of myoglobin by removal of the heme.
Hiroshi Imamura, Takeshi Morita, Tomonari Sumi, Yasuhiro Isogai, Minoru Kato,
Keiko Nishikawa
J. Synchrotron Rad. 20, 919-922 (2013).

178) 4,5-Dihaloimidazolium-based ionic liquids: Effects of halogen-bonding on crystal structures andionic conductivity.
Tomohiro Mukai and Keiko Nishikawa
RSC Advances 3, 19952–19955 (2013).
179) Determination of missing crystal structures in the 1-alkyl-3-methylimidazolium hexafluorophosphateseries: implications on structure-property relationships.
Takatsugu Endo, Hyuma Masu, Kozo Fujii, Takeshi Morita, Hiroko Seki, Sabyasachi Sen,
Keiko Nishikawa
Cryst. Growth and Design, 13, 5383−5390 (2013).
180) Fast Cation Dynamics in the Crystalline State of an Imidazolium-Based Room Temperature Ionic
Liquid due to the Presence of a Tiny Amount of H 2 O.
Takatsugu Endo, Mamoru Imanari, Hiroko Seki, Sabyasachi Sen, and Keiko Nishikawa
Solid State Ionics, 259, 41−45(2014)181) Crystal structure of 1,3-dimethylimidazolium bis(fluorosulfonyl)amide: unexpectedly high melting
point arising from polydentate hydrogen bonding
Kozo Fujii, Tomohiro Mukai, and Keiko Nishikawa
Chem. Lett. 43, 405–407(2014).
182) K-edge X-ray Absorption Fine Structure Analysis of Pt/Au Core-Shell Electrocatalyst: Evidence for
Short Pt-Pt Distance.
Takahiro Kaito, Hisashi Mitsumoto, Seiho Sugawara, Kazuhiko Shinohara, Hiromitsu Uehara,
Hiroko Ariga, Satoru Takakusagi, Yoshikiyo Hatakeyama, Keiko Nishikawa, Kiyotaka Asakura
J. Phys. Chem. C 118, 8481-8490 (2014).
183) Effect of Adding a Thiol Stabilizer on Synthesis of Au Nanoparticlesby Sputter Deposition onto
Polyethylene Glycol
Yoshikiyo Hatakeyama, Jun-ichi Kato, Tomohiro Mukai, Ken Judai, Keiko Nishikawa
Bull. Chem. Soc. Jpn. 87, No.7 773-779 (2014) (Selected Paper)184) How Much Weaker are the Effects of Cations than Anions? :The Effects of K+ and Cs+ on the
Molecular Organization of Liquid H 2 O
Takeshi Morita, Peter Westh, Keiko Nishikawa, Yoshikata Koga
J. Phys. Chem. B 118, 8744-8749 (2014).
185) Characterization of BF 4 – in terms of its effect on water by the 1-propanol probing methodology
Takeshi Morita, Ayako Nitta, Keiko Nishikawa, Peter Westh, Yoshikata Koga
J. Mol. Liq. 198, 211-214 (2014).
186) Microscopic Structure of Naked Au Nanoparticles Synthesized in Typical Ionic Liquids by Sputter
Deposition.
Yoshikiyo Hatakeyama, Kiyotaka Asakura, Satoshi Takahashi, Ken Judai, and Keiko Nishikawa
J. Phys. Chem. C 118, 27973-27980 (2014).
187) Model-Potential-Free Analysis of Small Angle Scattering of Proteins in Solution: Insight into
Solvent Effects on Protein-Protein Interaction.
Tomonari Sumi, Hiroshi Imamura, Takeshi Morita, Yasuhiro Isogai and Keiko Nishikawa
Phys. Chem. Chem. Phys. 16, 25492–25497 (2014).
188) Anion and Cation Dynamics of Sulfonylamide-Based Ionic Liquids and the Solid-Liquid Transitions.
Mamoru Imanari, Kozo Fujii, Tomohiro Mukai, Noriko Mizushima, Hiroko Seki, Keiko Nishikawa
Phys. Chem. Chem. Phys. 17, 8750–8757 (2015).

189) Structure and Dynamics of Room Temperature Ionic Liquids with Bromide Anion: Results from 81Br
NMR Spectroscopy.
Takatsugu Endo, Mamoru Imanari, Yuki Hidaka, Hiroko Seki, Keiko Nishikawa, Sabyasachi Sen
Magn. Reson. Chem., 53, 369–378 (2015).
190) Density fluctuations in Aqueous Solution of Ionic Liquid with Lower Critical Solution Temperature:
Mixture of Tetrabutylphosphonium Trifluoroacetate and Water.
Ayako Nitta, Takeshi Morita, Shohei Saita, Yuki Kohno, Hiroyuki Ohno, Keiko Nishikawa
Chem. Phys. Lett., 628, 108–112 (2015).
191) Absorption- and Pressure-Induced Structural Transition Exhibiting V-shaped Density Change in
Imidazolium-based Ionic Liquid + CO 2 System.
Shuhei Okumura, Masayoshi Ushio, Akina Oishi, Keiko Nishikawa, Takeshi Morita
Chem. Lett. 35, 937–939 (2015).
192) Excess Partial Molar Absorptivity of Aqueous Solutions of KCl, KBr, CsCl and CsBr: Are There
Three Universal Chromophores in the Excess Molar Absorptivity of the ν 2 + ν 3 Band of H 2 O for
Aqueous Salt Solutions?
Fumie Sebe, Keiko Nishikawa, Yoshikata Koga
J. Sol. Chem. 44, 1833–1843 (2015).
193) Asphaltene Aggregation Behavior in Bromobenzene Determined By Small-angle X-ray Scattering.
Masato Morimoto, Hiroshi Imamura, Satoshi Shibuta, Takeshi Morita, Keiko Nishikawa, Hideki
Yamamoto, Ryuzo Tanaka, Toshimasa Takanohashi
Energy and Fuels, 29, 5737–5743 (2015).
194) Phase Behavior of a Piperidinium-Based Room-Temperature Ionic Liquid Exhibiting Scanning Rate
Dependence.
Yuichi Shimizu, Kozo Fujii, Mamoru Imanari, Keiko Nishikawa
J. Phys. Chem. B 119, 12552–12560 (2015).
195) Anion and Cation Effects on Size Control of Au Nanoparticles Prepared by Sputter Deposition in
Imidazolium-based Ionic Liquids.
Yoshikiyo Hatakeyama, Ken Judai, Kei Onishi, Satoshi Takahashi, Satoshi Kimura,
Keiko Nishikawa
Phys. Chem. Chem. Phys. 18, 2339–2349 (2016).
196) Temperature-independent formation of Au nanoparticles in ionic liquids by arc plasma deposition.
Yoshikiyo Hatakeyama, Satoshi Kimura, Tatsuya Kameyama, Yoshiaki Agawa, Hiroyuki Tanaka,
Ken Judai, Tsukasa Torimoto and Keiko Nishikawa
Chem. Phys. Lett. 658,188–191 (2016).
197）NMR Study on Ion Dynamics and Phase Behavior of a Piperidinium-Based Room-Temperature Ionic
Liquid: 1-Butyl-1-methylpiperidinium Bis(fluorosulfonyl)amide.
Yuichi Shimizu, Yuto Wachi, Kozo Fujii, the late Mamoru Imanari, and Keiko Nishikawa
J. Phys. Chem. B 120, 5710–5719 (2016).
198) Comprehensive conformational and rotational analyses of the butyl group in cyclic cations:
DFT calculations for imidazolium, pyridinium, pyrrolidinium, and piperidinium.
Takatsugu Endo, Shinpei Hoshino, Yuichi Shimizu, Kozo Fujii and Keiko Nishikawa
J. Phys. Chem. B 120, 10336–10349 (2016).
199) Fluctuational parameters based on the Bhatia–Thornton theory for supercritical solutions:Application to a supercritical aqueous solution of n-pentane.

Satoshi Shibuta, Hiroshi Imamura, Keiko Nishikawa and Takeshi Morita
Chem. Phys. 487, 30–37 (2017).
200) Spectra of Excess Molar Absorptivity of Aqueous Solutions of Ionic Liquids:
Universal Chromophores for Aqueous Electrolytes?
Fumie Sebe, Keiko Nishikawa, and Yoshikata Koga
J. Mol. Liq., 238, 570–573 (2017).
201) Mixing scheme of an aqueous solution of tetrabutylphosphonium trifluoroacetate in the water-richregion.
Ayako Nitta, Takeshi Morita, Keiko Nishikawa, and Yoshikata Koga
Phys. Chem. Chem. Phys. 19, 16888–16896 (2017).
202) Band shift and bandwidth broadening in Raman spectra of CO 2 induced by absorption into an
imidazolium-based ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate, up to 15 MPa.
Sakitada Suzuki, Shuhei Okumura, Keiko Nishikawa, Hideyuki Nakayama, Takeshi Morita
Chem. Phys. Lett. 684, 346–350 (2017).
203) Effects of H+ and OH – on H 2 O as Probed by the 1-Propanol Probing Methodology: Differential
Thermodynamic Approach.
Yoshikata Koga, Kumiko Miki, and Keiko Nishikawa
Phys. Chem. Chem. Phys. 19, 27413–27420 (2017).
204) Effects of ionic liquid constituent cations, tetraalkylammoniums, on water studied by means of the“1-propanol probing methodology”.
Kazuki Yonenaga, Takeshi Morita, Keiko Nishikawa and Yoshikata Koga
J. Mol. Liq. 252, 58–61 (2018).
205) Growth Behavior of Gold Nanorods Synthesized by the Seed-mediated Method: Tracking ofReaction Progress by Time-resolved X-ray Absorption Near-Edge Structure, Small-Angle X-ray
Scattering, and Ultraviolet-Visible Spectroscopy.
Yoshikiyo Hatakeyama, Koh Sasaki, Ken Judai, Keiko Nishikawa, and Kazuyuki Hino
J. Phys. Chem. C 122, 7982–7991 (2018).
206) Reduction of mesoscopic structural fluctuation of liquid water induced by the large amphiphilicity
of ionic liquid cations.
Takeshi Morita, Kazuki Yonenaga, Ayako Nitta, Satoshi Shibuta and Keiko Nishikawa
J. Mol. Liq. 272, 425–429 (2018).
207) Fluctuations and Mixing State of an Aqueous Solution of Ionic Liquid Tetrabutylphosphonium
Trifluoroacetate around the Critical Point.
Ayako Nitta, Takeshi Morita, Hiroyuki Ohno, and Keiko Nishikawa
Aus. J. Chem. 72, 93–100 (2019)

II. Reviews1) Solution Chemistry from Viewpoint of Fluctuation. (in Japanese)
Keiko Nishikawa, Takeshi Morita
Molecular Science 6, A0054-1~9 (2012).
2) Crystal Polymorphism of 1-butyl-3-methylimidazolium hexafluorophosphate: Phase diagram,structure and dynamics.

Takatsugu Endo, Kozo Fujii, and Keiko Nishikawa
Aus. J. Chem. 72, 11–20 (2019)