ライフサイエンスコーパス: ligand field

1 oid environment with a mixed nitrogen/oxygen ligand field.

2 + ion in a tetragonally-distorted octahedral ligand field.

3 mutations do not directly perturb the Cu(II) ligand field.

4 dination sphere that sensitively perturb the ligand field.

5 id series in the underexplored square planar ligand field.

6 state lifetimes based on the symmetry of the ligand field.

7 fies the ion residing in an octahedral oxide ligand field.

8 l rearrangements of the diiron subsite CO/CN ligand field.

9 from an ideal octahedral (O(h) point group) ligand field.

10 ter rates corresponding to weaker equatorial ligand fields.

11 opper centers experience virtually identical ligand fields.

12 g in terms of strength and symmetry of their ligand fields.

13 barrier to populating a dissociative triplet ligand field ((3)LF) state from the lowest-energy triple

14 following excitation into the lowest-energy ligand-field absorption band; the time constant is found

15 mpounds derive in part from the strong axial ligand field afforded by the cyclopentadiene anions, and

16 ethods, density functional calculations, and ligand field analyses are combined to define the geometr

17 the light of the bonding scheme derived from ligand field analysis of the ab initio results.

18 A simple ligand field analysis of this change indicates that bind

19 However, ligand field analysis using the experimental data shows

20 inated within an unusual all-oxygen trigonal ligand field and are accessible to both inner- and outer

21 satisfying the dual requirements of a strong ligand field and chemical tunability of the compound's a

22 over, was promoted in the case of the weaker ligand field and depends on both the nature and position

23 s and total intensities allow changes in the ligand field and effective nuclear charge to be determin

24 uction of the geometric configuration of the ligand field and gives indirect information about the co

25 y maintaining a large separation between the ligand field and metal-to-ligand charge transfer (MLCT)

26 hort Cu-N distances, resulting in a stronger ligand field and reduced thermal accessibility of symmet

27 while mutation at position 754 disrupts the ligand field and solvation near the cofactor iron.

28 a promising approach for observing specific ligand field and vibronic excited state coupling effects

29 t-field calculations (CASSCF), we define the ligand-field and charge-transfer excited states of [Mn(I

30 oretical approach is based on an analysis of ligand-field and small-cluster Hamiltonians based on the

31 With no ligand-field argument to support such an assignment, a r

32 rly demonstrate the importance of tuning the ligand field around the dimetal center to maximize the p

33 transition metal (TM) ion, by an appropriate ligand field, as a means of achieving higher barriers.

34 ible at the transition state due to a weaker ligand field associated with the steric interactions of

35 ioisomeric linker alters the symmetry of the ligand field at the metal sites, leading to increases of

36 ehavior originates from the dominating axial ligand field at the O adsorption site, which leads to ou

37 Comparison of the ligand fields at the Fe(II) shows little difference betw

38 c and electronic structure--including a weak ligand field, availability of two water ligands at the b

39 al of dianionic borolide ligands to increase ligand field axiality, compared to monoanionic cyclic li

40 to occur preferentially to the lower energy ligand-field band due primarily to more favorable dipole

41 dination of one cysteine side chain and also ligand field bands (epsilon560 = 140 M(-1) cm(-1)) indic

42 (III) complexes to reveal otherwise obscured ligand-field bands can be a useful tool for the developm

43 The ligand-field bands indicate square-pyramidal coordinatio

44 Ligand field calculations using AOMX are used to assign

45 Although synthetic tuning of the ancillary ligand field can stabilize M-L multiply bonded complexes

46 Because of the substantially different ligand-field chemistry of Mg(2+) and Cu(2+), site disord

47 The strongest ligand field component is likely the single axial Se ato

48 ese data support the presence of an inverted ligand field configuration for the Ni-CH(3) Az species,

49 Zr exhibit unusual populations according to ligand field considerations, which reveal a high degree

50 ransition metal cations, it is seen that the ligand field contributions play an important role in the

51 single-molecule magnets by concentrating the ligand-field contributions above and below the equatoria

52 of these analytes with FLiNaK, particularly ligand field coordination.

53 nce (EPR) in tandem to examine the impact of ligand field (d-d) excited states on spin relaxation rat

54 Tuning the ligand field (Delta(O)) by steric and/or electronic effe

55 By analyzing the spectra in combination with ligand field density functional theory we find that the

56 that generate a sufficiently strong in-plane ligand field (dmpe = 1,2-bis(dimethylphosphino)ethane, L

57 An inverted ligand field drives this unique electronic structure, wh

58 splitting is determined by the differential ligand field effect of Cl(-) versus OH(-) on the Fe cent

59 the other posits the development of a strong ligand-field effect favoring the low-spin ground state.

60 norganic pigments: their ability to leverage ligand field effects in charge transfer states to create

61 und-state wave function of Cu(A) in terms of ligand field effects on the orbital orientation and the

62 een the different complexes, consistent with ligand field effects previously observed in luminescence

63 alculations suggest is the result of greater ligand field effects.

64 w temperature can be attributed to increased ligand-field effects, which dominate with continued vari

65 Ligand-field electronic absorption and magnetic circular

66 This paper reports the application of ligand-field electronic absorption spectroscopy to probe

67 onjunction with accurate synthetic models of ligand-field electronic excited states, leading to a rei

68 copy data on a recently developed octahedral ligand-field enhancing [Fe(dqp)(2)](2+) (C1) complex wit

69 From the ultrafast S K-edge absorption, the ligand field excited state is found to be highly delocal

70 nd relaxation to a pseudotetrahedral triplet ligand field excited state.

71 hese experimental results directly implicate ligand field excited states as playing a critical role i

72 In particular, we focus on the ligand field excited states that dominate the photophysi

73 transfer excited states than metal-centered ligand field excited states.

74 to reductive quenching of the lowest-energy ligand-field excited state of the Co(III) chromophore.

75 lectron transfer involving the lowest-energy ligand-field excited state of the Fe(II)-based photosens

76 most common electron donors, and mapping its ligand-field excited states is critical to designing don

77 ystematic destabilization of metal-localized ligand-field excited states such that the low-energy por

78 The ground-state and charge-transfer/ligand-field excited-state properties of the low-spin cy

79 However, the weak ligand field experienced by a 3d transition-metal such a

80 An analysis of the ligand field experienced by the uranium center using ab

81 The weaker ligand field experienced by the valence d-electrons of f

82 Ligand field expressions are derived that describe the b

83 noxide constitute a sensitive probe of trans ligand field, FeCO structure, and electrostatic landscap

84 mponents in imine-based ligands can tune the ligand field for a Fe(II) center, which results in both

85 sults highlight the utility of an equatorial ligand field for facilitating slow magnetic relaxation i

86 ) metal complex that prefers a square planar ligand field forms a CT salt by bridging to the iron com

87 P450 indicates that the stronger equatorial ligand field from the porphyrin results in a low-spin Fe

88 synthetic strategy where the strong uniaxial ligand field generated by the Ph(3) SiO(-) (Ph(3) SiO(-)

89 properly orient the substrate, allowing for ligand field geometric changes along the reaction coordi

90 ttern correlates with its distorted T-shaped ligand field geometry and accounts for the observed low

91 Exploration of inverted ligand fields helps us see the continuous, borderless tr

92 s: while bite-angle optimization weakens the ligand field in Co(III) complexes, the resulting lower-e

93 bins, indicates that azide exerts a stronger ligand field in hHO than in the globins, or that the dis

94 This suggests that the proximal ligand field in these CO adducts is weaker than that for

95 The ligand field in this complex is weak and the metal-ligan

96 us 3d(10) configuration features an inverted ligand field in which all five metal-localized molecular

97 formal Cu(III) complexes indicates inverted ligand fields in sigma(Cu-CH(2)) bonds.

98 ction leads to an increase in the equatorial ligand field, indicating that the site acquires a more t

99 omplexes enables an initial probe of how the ligand field influences the static and dynamic magnetic

100 e of the electronic structure properties and ligand-field interactions, as well as information about

101 monodentate isocyanide ligand, a very strong ligand field is created.

102 n the context of native ACS, and an inverted ligand field is proposed as a mechanism by which to gate

103 Teller (lattice) distortion in an octahedral ligand field is the active chemical driving force for th

104 of quenching of orbital angular momentum by ligand fields is observed to occur at approximately 40 K

105 gn of analogous compounds with even stronger ligand fields is one promising route toward identifying

106 The vanadium, in a distorted octahedral ligand field, is covalently bound to the active site ser

107 his 16-electron species features an inverted ligand field, is diamagnetic, and exhibits C(3v) symmetr

108 y(3+), and U(3+) metal ions within the axial ligand field lead to slow relaxation upon application of

109 The contributions of ligand field (LF) and the charge on the absorbing atom i

110 The MCD spectrum of biferrous MIOX shows two ligand field (LF) transitions near 10000 cm(-1), split b

111 CD, and VTVH MCD spectroscopies coupled with ligand-field (LF) calculations are used to elucidate cha

112 highly oxidizing nature of the lowest-energy ligand-field (LF) excited state of a first-row d(6)-low-

113 o conversion from the charge-transfer to the ligand-field manifold.

114 w-energy portions of the charge-transfer and ligand-field manifolds are at or near an energetic inver

115 etation of the long-lived excited state as a ligand-field metal-centered quintet state.

116 ata highlight the inadequacy of the standard ligand field model that is often used to explain the ele

117 Thus, in agreement with the inverted ligand field model, the data presented herein imply that

118 ed some to a Cu(I) assignment in an inverted ligand field model.

119 In contrast, empirical ligand-field molecular mechanics (LFMM) captures the d-e

120 study, molecular dynamics simulations using ligand-field molecular mechanics are performed to elucid

121 soft donor that responds to the rest of the ligand field much more than stronger, harder donors like

122 Combined X-ray absorption spectroscopy and ligand field multiplet calculations show that Cu(II), Ni

123 The ligand field multiplet model commonly used to simulate L

124 e line splittings can be understood within a ligand field multiplet model, i.e., (3d,3d) and (2p,3d)

125 aracteristic of high spin Fe(3+) in a strong ligand field of low (orthorhombic) symmetry.

126 its importance, not much is known about the ligand field of the azido ligand and its influence on ma

127 transition states resulting from the weaker ligand field of the halogenase.

128 dentate ligands that modulate the equatorial ligand field of the Mn(IV) center, as assessed by electr

129 1-, 0, 1+, 2+), in which the weak, trigonal ligand field of the sulfides enforces high-spin configur

130 discussions about how to accurately tune the ligand fields of single-atom TM(4d,5d) sites in order to

131 ation complexes, with the resulting enhanced ligand fields often contributing to extended excited-sta

132 yl)(4) systems illustrates the impact of the ligand field on both the ground state spin structure and

133 assigned to activated surface crossing to a ligand field or MLCT excited state.

134 as having the same symmetry as the nominal "ligand field" or "d-d" states that typically dominate th

135 5) vs 5f(5) electron-counts within conserved ligand fields over 12 complexes.

136 The Fe ligand field overcomes the spin-forbidden nature of the

137 plexes, a switch in the sign of the dominant ligand field parameter and striking variations in the si

138 data to derive a new uranium-specific set of ligand field parameters (U)E(L)(L) that more accurately

139 ignment of its absorption bands leads to the ligand field parameters Delta(o) = 24800 cm(-1) and B =

140 scopy has been used to study changes in Co2+ ligand-field parameters as a function of alloy compositi

141 ased on the visible-near-IR spectra to yield ligand-field parameters for these complexes following th

142 A recent focus on ligand-field photocatalysis using cobalt(III) polypyridy

143 s in transition metal complexes from dynamic ligand field principles.

144 This demonstrates that the axial ligand field provided by an imidazole and a thioether is

145 mate substitutions indicate that the neutral ligand field provided by the protein optimizes the elect

146 A ligand field rationalization is advanced and supported b

147 of iron(II) are exposed to a relatively weak ligand field, rendering nonradiative relaxation of MLCT

148 consequences of such drastic changes to the ligand field represent important new opportunities in de

149 and Eu(DPA)(+), which was monitored via the ligand field sensitive (5)D0 --> (7)F3 transition (lambd

150 The ligand field shifted luminescence was excited using 1 mW

151 The ligand field spectra for the Mn(III) ion, characteristic

152 Core-level ligand field splitting allows direct access of excited s

153 spin model complexes revealed a reduction in ligand field splitting of approximately 1 eV in the high

154 ging objective due to the intrinsically weak ligand field splitting of first-row transition metal ion

155 th Brewer-type Ti-Ru interactions as well as ligand field splitting of the Fe 3d orbitals regulated t

156 heory-that thermal energy is larger than the ligand field splitting-does not hold for the lanthanide

157 ead, the dithiolene ligands define the t(2g) ligand field splitting.

158 r to restrict the magnitude of the d-orbital ligand-field splitting energy (which tends to hinder the

159 because relativistic effects, spin-orbit and ligand-field splitting, and complex metal-ligand bonding

160 ate is essential for determining the role of ligand-field splitting, multiconfigurational behavior, a

161 III) and chromium(III) species show that the ligand field splittings Delta(o) caused by the M-H-B int

162 the molecular orbital construction of these ligand field splittings evolves a strategy for inverting

163 odulation of the stability of the hexamer by ligand field stabilization effects.

164 lity of the ligand sphere and the absence of ligand field stabilization energies in systems with fill

165 These studies establish that ligand field stabilization energy (LFSE), coordination g

166 , the expectation based on considerations of ligand field stabilization energy.

167 o(2+)) is proposed to reflect differences in ligand-field stabilization energies (LFSEs) due to compl

168 They describe the ligand-field stabilization energy to an accuracy of abou

169 which show that the CT state is mixed with a ligand field state (t(2g) --> e(g)) by configuration int

170 Relaxation dynamics of an optically excited ligand field state and strong modulation of oscillator s

171 Excitation of the ligand field state created a coherent acoustic phonon re

172 frared pump beam prepared the lowest excited ligand field state of Fe(3+) ions preferentially on the

173 = 190 +/- 50 fs for the formation of the 5T2 ligand-field state was assigned based on the establishme

174 ons (for example, TiO(2) and BiVO(4)), where ligand field states are absent.

175 be explained by drastic modification of the ligand field states due to the fluoride binding.

176 econd relaxation mechanism via metal-centred ligand field states that compromise quantum yields in op

177 ious metal photocatalysts despite low energy ligand field states.

178 manifold at a faster rate than relaxation to ligand field states.

179 ion of the relative energies of the MLCT and ligand-field states across the series, leading to a syst

180 destabilizes the non-radiative metal-centred ligand-field states.

181 the increasing effective nuclear charge and ligand field strength allow us to control the energetic

182 re established approaches such as optimizing ligand field strength and coordination geometry is the u

183 (3)MLCT lifetime gets longer with increasing ligand field strength and improved steric protection, th

184 lar orbital (LUMO) energy is governed by the ligand field strength and is related to Lewis acid/base

185 l magnetic anisotropy scales with increasing ligand field strength at the iron(II) center.

186 , MCD data show that there is an increase in ligand field strength due to an increase in coordination

187 Similar ligand field strength in the mutant and the wild type (f

188 leotide binding environment with the highest ligand field strength is compatible with a metal coordin

189 Furthermore, ligand field strength is revealed to be a particularly p

190 age serves to markedly enhance the effective ligand field strength of His-18.

191 n fold and perhaps to increase the effective ligand field strength of Met-80 as well.

192 orm from planarity, which is imparted by the ligand field strength of the coordinated OH(-), is likel

193 These findings suggest that if the ligand field strength of the coordinated OOH(-) in heme

194 [((H)L)2Fe6(L')m](n+) in which the terminal ligand field strength was modulated from weak to strong

195 insights into how effective nuclear charge, ligand field strength, and ligand pai-conjugation affect

196 square-planar Cu(II) compounds with varying ligand field strength, including CuS(4), CuN(4), CuN(2)O

197 the coordinated hydroxide ligand, lowers its ligand field strength, thereby increasing the field stre

198 a previously unreported competition between ligand-field strength and metal-ligand (Fe-N(amido)) cov

199 endence is caused by modulation of the axial ligand-field strength by Lewis acid-base interactions be

200 was estimated, indicating a reduction in the ligand-field strength of ca. 3000 cm(-1) upon replacing

201 l complexes revealed significantly different ligand field strengths due to either diminished ligand s

202 Compounds with varying ligand-field strengths were prepared and studied using v

203 H dependence (pH approximately 6.5-9) of its ligand-field symmetry (rhombicity Delta delta = 10%, der

204 We construct several examples of inverted ligand field systems with a hypothetical but not unreali

205 It is found that the ligand field term dominates the edge energy shift.

206 rt a vanadium complex in a nuclear-spin free ligand field that displays two key properties for an ide

207 is phenomenon is attributable to an inverted ligand field that gives the bond Co(delta-)-C(delta+) ch

208 In contrast, ligand fields that are sufficient to stabilize the (3)T(

209 al metal-ligand interactions and a classical ligand field, the Ni-CH(3) hyperfine interactions betwee

210 computational methodology based on multiplet ligand field theory and maximally localized Wannier orbi

211 ienced by the uranium center using ab initio ligand field theory in combination with the angular over

212 On the basis of the ligand field theory, most fluorescence spectral peaks co

213 A simple ligand field theory-based design principle for electroca

214 ransitions were assigned with the aid of the ligand-field theory.

215 In the tetragonal ligand field, these electrons populate an orbital of dxy

216 these compounds arise from a single ion in a ligand field, they are often referred to as single-ion m

217 lifetimes, but as amido donors exert a weak ligand field, this defies conventional photosensitizer d

218 on approaches to impart sufficiently strong ligand fields to generate electron-rich metal complexes

219 PhBP(3)] ligand provides an unusually strong ligand-field to these divalent cobalt complexes that is

220 PR) spectra, which result from their similar ligand field transition energies and ground-state Cu cov

221 elative to the Cu(H) site leading to similar ligand field transition energies for both sites.

222 probe beam monitored the dynamics of various ligand field transitions and modification of their oscil

223 the low-energy region where Co(2+)-centered ligand field transitions are expected to occur.

224 strong modulation of oscillator strengths of ligand field transitions by coherent acoustic phonon in

225 We found that materials with spin-forbidden ligand field transitions could partially mitigate this r

226 pecies is characterized by a distinct set of ligand field transitions in the near-IR spectral region

227 We can unequivocally assign them to the ligand field transitions of dxy --> dxz,yz, dxz,yz --> d

228 trongly modulated oscillator strength of the ligand field transitions rather than oscillating Frank-C

229 spectroscopy revealed the presence of Co(II) ligand field transitions that had molar absorptivities o

230 e transfer band and (2) less intense, Co(II) ligand field transitions that suggest 4-coordinate Co(II

231 Contrastingly, the Co(2+)-centered ligand field transitions, which are observed here for th

232 Identification of any three ligand-field transitions allows for the determination of

233 c circular dichroism (MCD) spectra show weak ligand-field transitions between 5000 and 12,000 cm(-1)

234 efects, transient light-induced defects, and ligand-field transitions in the inorganic layers and mol

235 ns in the UV region and (5)T(2g) --> (5)E(g) ligand-field transitions in the NIR region at 12400 and

236 donor emission spectra and the two observed ligand-field transitions of the Cu(II) ion.

237 hat GPh degradation can be optimized through ligand field tuning in MOFs, which can help improve over

238 By precisely tailoring the ligand fields using sodium dimethyl dithiocarbamate (SDD

239 ss larger series of complexes in response to ligand field variations.

240 ron transfers is stabilized by an octahedral ligand field, whereas in the solution phase a Pt(II) met

241 urally from a semiclassical treatment of the ligand field, which becomes valid in the limit of large

242 Combining a strong axial [Cp*](-) ligand field with a weak equatorial field consisting of

243 ground state (S = 5/2) for Mn2+ and a strong ligand field with large anisotropy.

244 Coupling this strong ligand-field with a pronounced axial distortion away fro

245 rmazanate ligand, resulting in an "inverted" ligand field, with an approximate "two-over-three" split

246 s provide the first evidence for an inverted ligand field within a biological system.