Intriguing electric field effect on magnetic spin couplings in dielectron clathrate hydrates

Abstract

Clathrate hydrates have appeared as promising icy materials as the radical, high-spin molecule, and even electron clathrate hydrates are found. In particular, dielectron clathrate hydrates are expected to develop as structural units for a novel class of icy magnetic materials because of not only possible spin coupling interaction, but also very sensitive response to electric field of the loosely bound electrons. However, electric field responses concerning the magnetic properties of such hydrates have not been reported so far. In this work, three representative dielectron clathrate hydrate model clusters (e 2 @4 6 6 8 BB, e 2 @5 12 6 2 BB, and e 2 @4 6 6 8 AB) were considered for the exploration of their magnetic spin coupling properties, electron distributions, and energy responses to applied electric field. The results calculated at the density functional theory level show that the energies and electron spin coupling properties of these dielectron clathrate hydrate clusters are quite sensitive to applied electric field, presenting intriguing variations. Most importantly, applied electric field can regulate the strength of spin coupling between two trapped electrons, and even could realize the magnetic interconversion of such dielectron cluster structures between antiferromagnetic and paramagnetic or diamagnetic characteristics. Clearly, the intriguing variations should be attributed to the diffuse character, special mobility and polarizable properties of such trapped electrons, and especially the susceptible redistributions of two electrons (including the electron cloud shape and distance between two electron centers) to the electric field. This work opens up the possibility of designing novel icy magnetic materials with sensitive electric field responses of the magnetic properties. K E Y W O R D S density functional theory calculation, dielectron clathrate hydrate cluster, electric field effect, magnetic spin coupling, through electron-permeating H-bond coupling channel 1 | INTRODUCTIONRecently, clathrate hydrates have been highly valued by both theoretical and experimental researchers [1][2][3][4][5][6][7][8][9][10][11] because of the gas storage capacity and potential applications in icy materials. [9] In such clathrate hydrates, water molecules as host molecules form a water cage through intermolecular hydrogen bonding to wrap various guest molecules, and the distance between two adjacent cages is generally 6 to 10 Å, such a distance is likely to lead to interactions between the guest species of the clathrate hydrate cavities. Clathrate hydrates encapsulating free radicals, high-spin substances, charged ions, or even excess electrons (EEs) are likely to exhibit rich magnetic properties [12][13][14] and other properties. [15,16] As a

Solvated electrons in the complex media: a review

“…图 13 酰胺-Ca 2+ 水溶液中过剩电子不同的定域化模式 [69] (网络版彩图) [70] (网络版彩图) [37] (网络版彩图) 图 16 吡啶型离子液中开壳层单态及三态的双极化子结构特征(a)及两种状态模拟轨迹中对应的瞬态构型的开壳层单态及三 态的相对稳定性(b, ΔE>0表示三态稳定) [75] (网络版彩图) 图 17 单笼结构的水合电子和水合双电子(a)及双笼结构的开壳层单态(BS)及三态(T)水合电子对(b) [63] (网络版彩图) [76,77] (网络版彩图)…”

“…Figure 18 The representative dielectron clathrate hydrate bi-cavity structure, spin density distribution and the spin coupling pathway of two electrons (a) and the electric field regulated changes of spin denisty and spin coupling contants (b) [76,77] (color online). [63] (网络版彩图) [78] (网络版彩图)…”

“…Figure 23 The spin coupling mechanism of hydrated dielectron [76,77] (color online). [85] (网络版彩图) [93] (网络版彩图)…”

Magnetic Dioxygen Clathrate Hydrates: A Type of Promising Building Blocks for Icy Crystalline Materials

“…These crystalline water-based solids are thought to be ubiquitous on earth, especially on the ocean floor and within the surface layer of the permafrost regions. It is conservatively estimated that the energy thought to be contained in natural CHs is double that of currently recoverable worldwide fossil fuels. , Beyond on earth, CHs were also identified on comets, Mars, and other outer planets. − Thus, CHs are viewed as a potential energy resource for the future, such as future clean energy resource , and gas transportation. , To date, a large number of the guest molecules (CO 2 , CH 4 , CO, H 2 , and N 2 ) encaging CHs have been investigated in order to explore their structures and inherent nature of inclusion phenomena. − A particular type of CHs in this category is the magnetic ones, which contain free radicals, high-spin substances, or excess electrons in their stacked nanocages, exhibiting unusual and discrete magnetic phenomena. − Molecular oxygen, O 2 , is the simplest magnetic molecule with a spin S = 1 in its ground state, and its magnetism in the confined states absorbed in one-dimensional channel and two-dimensional layer structures or in solid state was investigated. − It should be noted that several O 2 CHs (O 2 @CHs) were prepared with experimental characterization of structures and properties, ,− revealing the possibility of preparing O 2 @CHs with target structures and properties. However, information about the structures and properties of such magnetism-suspected CHs, especially the associated magnetic properties, are quite scarce.…”