我需要绘制一个方案来显示乙酸根离子通过共振而稳定,我快要疯了 :-( 我不久前开始使用 chemfig,看来我需要更多的练习!与此同时,有人能帮我解决这个问题吗?我想要这样的东西
但是我添加第一个箭头就已经失败了 :-(
\documentclass{article}
\usepackage{chemfig}
\begin{document}
\schemestart
\chemfig{R-C(=[1]{@{a1}\lewis{2:0:,O}})[@{db}](-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\ominus}}}})}
\arrow{<->}
\chemfig{R-C(=[1]{\lewis{2:0:,O}})(-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\ominus}}}})}
\arrow{<->}
\chemfig{R-C(=[1]{\lewis{2:0:,O}})(-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\ominus}}}})}
\schemestop
\chemmove{\draw(db).. controls +(100:5mm) and +(145:5mm).. (a1);}
\end{document}
答案1
大概是这样的?
\documentclass[
crop,
border=5,
tikz=true,
multi={page},
12pt
]{standalone}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{amsfonts}
\usepackage{mathtools}
\usepackage{chemmacros}
\chemsetup{
modules = all,
}
\usepackage{chemfig}
\setchemfig{
angle increment = 15,
atom sep = \bndlen,
bond offset = 0.5pt,
double bond sep = 3pt,
compound sep = 5.0em,
arrow coeff = 1,
arrow offset = 12pt,
scheme debug = false,
bond join = true,
chemfig style={line width=\lnwidth},
arrow style={line width=\lnwidth},
}
\newcommand{\bndlen}{2.0em}
\newcommand{\lnwidth}{0.7pt}
\begin{document}
\begin{page}
\schemestart
\chemleft{[}
\subscheme{
\chemfig{
CH_3
-C
(-[::-45]\lewis{1:5:7:,O}\rlap{\color{purple}{${\ }^-$}})
=[@{b1}::45]@{o1}\lewis{1:3:,O}
}
\arrow{<->}
\chemfig{
CH_3
-C\rlap{\color{teal}{${}^+$}}
(-[@{b2}::-45]\lewis{1:5:7:,O}@{o2}\rlap{\color{purple}{${\ }^-$}})
-[::45]\lewis{1:3:7:,O}\rlap{\color{purple}{${\ }^-$}}
}
\arrow{<->}
\chemfig{
CH_3
-C
(=[::-45]\lewis{5:7:,O})
-[::45]\lewis{1:3:7:,O}\rlap{\color{purple}{${\ }^-$}}
}
\chemmove{
\draw[shorten <=3pt,shorten >=1pt,purple](b1)..controls +(-15:10mm) and +(-30:5mm)..(o1);
\draw[shorten <=3pt,shorten >=1pt,purple](o2)..controls +(90:5mm) and +(45:5mm)..(b2);
}
}
\chemright{]}
\schemestop
\end{page}
\end{document}
此外,如果您追求完美的复制品,请注意插图中使用的字体系列很可能是专有的新巴斯克维尔 ITC。要使用它,您必须获取字体或使用免费替代品LaTeX 字体目录;此时使用 XeLaTeX 进行编译会更容易。
答案2
以下是第一步反应的两种可能版本,箭头有两种变体。但确切的参数可能仍需要进行一些微调。
\documentclass{article}
\usepackage{chemfig}
\begin{document}
\schemestart
\chemfig{R-C(=[@{db}1]{@{a1}\lewis{2:0:,O}})(-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\ominus}}}})}
\schemestop
\chemmove{\draw(db).. controls +(100:5mm) and +(145:5mm).. (a1);}
\vspace{1.5cm}
\schemestart
\chemfig{R-C(=[@{db}1]{@{a1}\lewis{2:0:,O}})(-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\ominus}}}})}
\schemestop
\chemmove{\draw[shorten <=4pt,shorten >=4pt](db).. controls +(10:5mm) and +(-10:10mm).. (a1);}
\end{document}
配色:
\documentclass{article}
\usepackage{chemfig}
\begin{document}
\schemestart
\chemfig{R-C(=[@{db}1]{@{a1}\lewis{2:0:,O}})(-[7]{\lewis{0:4:6:,{\chemabove{O}{\scriptstyle\hspace{3mm}\color{red}\ominus}}}})}
\schemestop
\chemmove{\draw[shorten <=4pt,shorten >=4pt, color=red](db).. controls +(10:5mm) and +(-10:10mm).. (a1);}
\end{document}